lars

Forum Member jmgvreer1 (Jay) had some questions about rebuilding his Q-Jet in his thread here:

https://www.corvetteforum.com/forums...rebuild-2.html

After sitting for many years, the carb was clearly having some problems, and this is not surprising. He ended up sending it out to me for a checkover and setup, and is allowing me to share the inspection, rebuild, and test process with you here in this thread.

Jay’s car is a 1973 base 350. It’s all stock with the automatic. Carb seems to be running rich, and leaking fuel. Here it is in the as-received condition:




Carb number on the carb is 17054919 with date code 2214. This is a correct GM Service Replacement (aka, “SR”) carb for the 1973 Corvette 350. The SR carbs were manufactured exactly like the original carbs, and had the same specs and configuration as the carb they were intended to replace. This carb is the factory replacement for the 7043202 And 7043203. The date code (2214) indicates that it was built on the 221st day of a year ending in “4.” All Q-Jets built in the 1970’s had slotted head hardware in the airhorn. Q-Jets built in the mid- and late-80’s used Torx screws in the airhorn. We can determine, therefore, that this SR carb was built on the 221st day of 1984. It is in very nice condition, with no corrosion, and all plating in nice shape:


Initial inspection revealed that the secondary airvalves were jammed and locked by a slight distortion of the airhorn casting: A slight over-tightening of the 2 rear airhorn screws has distorted the casting just enough to jam into the rear edge of the airvalves, locking them in the closed position. The secondaries on this carb are inoperative:


“Smacking” the airvalves knocked them loose, but the distorted casting will not allow them to close now. We have to fix this:


Removing the inlet fitting and filter revealed 2 things:

The inlet fitting seal is broken, contributing to fuel leakage. Note also the broken vacuum fitting cap, providing a vacuum leak:


Attempts to blow through the filter revealed that the filter is completely plugged – no air can be blown through the filter at all.


Carb was then disassembled. The only “trick” to removing the airhorn on post-’69 Q-Jets is that the accelerator pump arm must be removed since there is no retaining clip on the pump arm rod. A pin punch and hammer are used to push the roll pin in to remove the arm:


Airhorn removed, and carb ready for inspection and final disassembly:


Testing the adjustment height of the power piston, also known as “Adjustable Part Throttle” (APT) position, shows that the piston is set to ride a little “low” at part-throttle cruise. This will make the engine run lean, especially with ethanol-enhanced pump gas:


Float needle clip was correctly installed, indicating that the carb has either never been rebuilt, or was previously worked on by someone who knew what they were doing. Incorrect installation is when the clip is installed through the slotted holes in the float arm or around the front, flat edge of the arm:


Float level isn’t too bad, but a little on the low side for a performance application:


Removal of the float showed massive contamination and debris in the bottom of the bowl. This was also contaminating the needle/seat surface, causing loss of fuel level control:


Carb disassembled and ready for hot tank cleanup. With the carb disassembled, all jetting/rod components are inspected for proper size and spec: It is imperative that you know what the spec sizes are in order to identify potential problems. The "spec" primary jet/primary rod/secondary rod sizes for this carb are 74/44/DA. This carb had sizes 74/43/DA. The non-spec primary rod is very common, and is not an issue or concern in this case: Most 7043202 carbs I have documented came with the slightly-rich primary rods, which will work to our advantage on this build.This is a very nice, original carb with very few problems – a perfect candidate for a nice rebuild and setup:


More to come as assembly starts after cleanup…

Lars

Greg

Lars, thanks again for another one of these "follow alongs". I'm sure all the guys enjoy them as much as I do, especially when you find a mostly undisturbed original like this one.
Cheers, Greg

'73and'75

Thank you Lars for sharing. I learn new things with every one of these threads you post. Your attention detail is admirable.

lars

Here is another inspection tip for those of you building carbs and tuning engines:

Notice in the photos above how there is a significant amount of black exhaust reversion sooting in the carb's throttle bores. The primary venturies and bores are completely black, with the secondary bores also showing black sooting:


This is a good indicator of engine tuning issues not related to the carb, usually retarded timing. Jay admits in his note that he sent me with the carb that he has not yet checked or adjusted the timing on the car, and the evidence in the carb proves that it needs to be done. Correctly setting up the timing and the timing curve has a HUGE impact on the vehicle's performance, and will usually affect power much more than a good carb setup. Even the best carb setup cannot compensate for badly set timing, so Jay is going to make it a priority to get the timing right once he gets the carb back.

Carb is still cleaning up... the cleanup is revealing a little more surface corrosion than initially thought, so a little extra cleanup attention will be given to the carb to make it look nice again.


Lars

lars

All parts cleaned and de-rusted. Near-new condition with good plating and color. The "Torx" airhorn screws are still rusty, so I will be re-applying a black oxide finish to those to make them look new again. Ready to start assembly and setup!

interpon

Thank you for taking time and offering service and advice..
mine’s still perfect. Cant wait for owner to report running!

Capt. Shark

I always enjoy these.

Catfish4818

This almost makes me wish I had a Qjet needing rebuilding.

Jebbysan

I have one on the bench right now.......they are a blast to build if you have a nice core, and good means to clean one.
The owners carb here in the picture is representitive of a SUPER nice core.......a huge tell on these is the screws that it is held together with. If they do not look like the original pieces, run from it.
I wish I had time to search and buy cores all day......it is a huge hole in the vintage Chevy hobby not having new pieces available.

Jebby

OMF

Following along.....

shoptek

These "follow along" carb posts from Lars are THE BEST! Great learning experience

lars

The process of “rebuilding” a carb is not a matter of throwing the parts in a bucket of cleaner and then re-assembling them with a new set of gaskets, aka, “installing a carb kit.” The process entails identifying and correcting all issues and problems with the carb, and any antique 50-year-old carb will have problems. If you re-assemble the carb the same way you took it apart, it’s going to have the same problems as it did before you started.

Let’s start with the lowly throttle plate. This poor assembly never gets any attention during rebuild, yet it gets lots of attention from hackers who want to screw up a carb. Problems with the throttle plate will affect secondary operation, idle speed control problems, and cruise mixture problems. Most throttle plates have been altered in some way, and you have to identify and fix these alterations. Jay’s carb is a very original carb, yet the throttle plate still has problems…


On a bare throttle plate assembly, with no idle speed screw limiting throttle closure, all 4 throttle blades should be firmly and tightly centered and nested in their respective throttle bores when the throttle is closed. To check for this, simply hold the primary throttle lever closed and hold the throttle plate up to a light or against the sky: There should be almost no “light gaps” around any of the 4 throttle blades. Any gap around the blades is a vacuum leak, and it will affect your ability to control idle rpm. Gaps are caused by several things:

1. Improperly aligned throttle blades. The blades have often been removed and improperly installed. If the blades are “cocked” in the bores, they will not close properly. They must then be loosened and re-aligned in their bores until they seal and align. Be aware that the screws holding the blades to the shafts are staked, so you cannot remove the screws without grinding the stake feature off the ends of the screws. However, the screws can usually be safely loosened about ¼ turn without grinding the stake, and without breaking the screws. If you break the screws off in the shaft, you are “screwed.” So wiggle the screws back and forth, using a little “feel” and gentleness, until you get each screw loosened about ¼ turn. You can then “wiggle & jiggle” the blades to get them to align themselves in the bores before snugging the screws back down.

2. Bent throttle blades. I see this more often than you would imagine. All 4 throttle blades should be perfectly flat. If any blades are bent, you need to replace them. This will require grinding the staked ends of the screws and a donor carb with good throttle blades. Inspect all 4 blades for flatness.

3. Finally, there is the issue of improperly adjusted throttle linkages. Carb hackers just LOVE to “tweak” and alter the linkages on Q-Jets, thinking that they are “fixing” the secondary operation. Many of these “fixes” actually prevent secondary operation, and cause other problems. Here is the “light gap test” on Jay’s carb. Note the light gaps around the primary throttle blades in the bores – the throttles cannot be fully closed, and this will affect the ability to set minimum idle speed on this carb:


The linkage parts that affect the ability to fully close the primary throttle are the secondary actuation rod:


…and the secondary closure tang:


This tang forces the secondaries to close when the primary throttles are closed. If the secondary actuation link has been shortened, and/or if the closure tang has been bent forward, the primary throttle cannot be fully closed. In this case, you can see in the photo that the tang has been bent forward. This is putting tension on the secondary actuation rod, and is preventing full throttle closure. The tang must be bent back to allow the primary throttle to fully close, and still have a very slight air gap between the tang and the actuation lever for a little bit of “rattle room:”


The tang has here been bent to its correct position, and the primary throttles can now be fully closed:


The next thing we need to check is the “secondary crack-open” feature. Under certain conditions, when gradually “tipping into” the throttle at elevated rpm, engine vacuum can be high enough to hold the secondary throttles closed and prevent them from opening: The secondary actuation rod is placed very low on the secondary throttle lever, and has very little leverage as seen here:


If engine vacuum is high enough, the lever springs will allow the secondary throttle lever to simply spin on the throttle shaft, and the throttle will remain closed. So a “crack-open” lever is provided to force the throttle blades open under vacuum. This tang at the top of the lever, actuated by the vertical portion of the secondary actuation rod, is the “force-it-open” feature:


Before the throttle linkage actuates the secondaries, the secondary actuation rod is “at rest” in this forward position in the secondary throttle lever slot:


This leaves the throttles fully closed, and held closed by manifold vacuum:


As the throttle is opened into the secondaries, the actuation rod moves back and contacts the “force-open” tang at the top of the lever, putting a lot of force on the secondary throttle lever:


Further moving the throttle pushes the secondary actuation rod through the travel allowed by the slot, and the amount of this travel is the amount that the secondary throttles are forced open by the tang at the top of the lever:


If you notice in the photos above, Jay’s carb has a very large gap between the vertical portion of the secondary actuation rod and the “force-open” tang, which means that the rod movement allowed by the slot has been mostly “consumed” before the throttle is ever forced open. If the throttle does not get enough (or any) “force-open” movement, manifold vacuum can still hold the secondary throttle closed. Here is the amount of gap created in the secondary throttle on Jay’s carb:


This is so little movement, and such a small crack-open amount, that there is a possibility that Jay’s secondaries could fail to open. To correct this, either the tang on the lever can be bent a little forward, or the vertical portion of the secondary actuation rod can be tilted back to narrow the gap between the two components. Here the rod has been tilted back just a tad, and the gap has been narrowed to just a small gap between the two – you MUST have a little gap, or the secondary throttle will be held partially open at all times, which will really screw up your idle speed:


This geometry correction now forces the secondary throttle to crack open enough to release any amount of manifold vacuum attempting to hold them closed:


Then there is the issue of how far the secondary throttles are allowed to open. The common “speed trick” on Q-Jets is to bend the linkage to make the secondaries open sooner and further. Correctly adjusted, the secondaries should open just short of vertical. Not past vertical. Here is a common misadjusted secondary throttle travel on Jay’s carb. Note that the throttle blades, in the fully-open position, have gone past vertical:


The travel range of the secondary throttle is adjusted by a tang, which is actuated by the secondary closure tang:


By bending this tang back just a little, the correct secondary throttle opening angle can be achieved: The “correct” secondary full-open blade angle is achieved when the top edges of the throttle blades point towards the lower edge of the air baffle located in the secondary venturies of the float bowl. Here I’m holding the air baffle from the bowl, showing that the throttle blades’ top edges should point towards the lower edge of the baffle. This position and angle results in the smoothest, least turbulent airflow through the secondary side of the carb, which results in the maximum cfm flow capacity:


Here the “just-short-of-vertical” correct wide open throttle blade angle can be seen. Compare this to the photo above with the incorrect over-center angle:


Finally, we need to look at the APT setting on the carb. If you remember from the initial posting and photos above, the “Adjustable Part Throttle” height of the power piston needs to be set correctly in order to achieve proper light throttle cruise air/fuel mixture. The factory set these carbs up to be a bit on the lean side in order to achieve reasonable fuel economy. With the use of ethanol-enhanced pump gas, this setting produces an over-lean condition at cruise, with resultant poor throttle response and possible lean-surging at cruise. This is a typical factory setting on the piston height, as is present on Jay’s carb:


On 4MV carbs (divorced choke) this height position is determined by the power piston’s stop pin riding on the APT adjustment tang in the throttle plate:





On 4MV carbs, inside the throttle plate, behind the little steel plate that’s staked into the center front surface of the throttle plate (seen in photo above), there is an adjustment screw that will allow you to raise or lower the tang, thus changing the power piston height. However, this screw is almost always rusted and seized in place, and is virtually unusable. Don’t bother trying. Instead, the power piston height can be changed by simply and carefully bending the tang a little. Here I’m using a small screwdriver to raise the tang to the position I desire:


Here is my preferred position of the tang:


This results in the power piston being raised to a height that has the inner brass sleeve of the piston riding about .020” - .030” above the top lip of the plastic retaining collar:


Obviously, the “perfect” APT setting cannot be achieved without actually running a wide-band A/F monitor in the car at cruise, but this bench setting has proven to be a very good general setting for virtually all applications.

When inspecting the power piston, make sure your piston actually has the stop pin intact. It is a popular “trick” to cut the pin off the piston with a pair of sidecutters. This completely messes up your cruise mixture, and makes it uncorrectable. If you have a piston with a cut pin, throw it away and get a replacement from a good carb. Here you can see the difference between a correct piston with pin and one that has been destroyed by a “rebuilder”:


Next segment will get the carb assembled… finally…

Lars

lars

With the throttle plate correctly set up, it’s time to move on to the float bowl. This is where a lot of modifications and “terminal” alterations are done with drilling of orifices, removal of air and fuel bleeds, and other hard-to-detect weird-*** work. The task of the carb builder then becomes to be a good enough detective to spot all the problems, which can be tricky even for an experienced builder. Luckily, Jay’s carb has not been hacked and altered, so we can just do some basic verifications to assure that it will run right.

One of the most critical features of the float bowl is the fuel restriction system for the idle fuel system. Fuel for idle and transition circuits goes down through the main metering jets into a fuel “well” below the jets. Engine vacuum from below the throttle blades pulls this fuel up out of the well, through an Idle Fuel Restrictor (IFR) tube orifice, up to the top surface of the float bowl, where the airhorn provides a “U-Turn” passage to send the fuel back down a parallel passage to the idle mixture screws and idle fuel discharge orifice. The metering orifice at the bottom of the IFR is the smallest fuel metering orifice in the carb, and it’s the one most susceptible to getting plugged: Sizes of the IFRs vary in the mid-.030” - .039” range. A buildup in the IFR of only a few thousands of an inch will dramatically change the idle fuel flow, and can make the idle mixture screws ineffective and unresponsive. The IFR tube is located here:


Many “rebuild kits” include new IFR tubes. Here is a commonly-supplied replacement tube. You can clearly see that the upper orifice hole in the tube is nowhere close to the correct size. Replacing your stock tube with incorrect aftermarket parts can have a severe and adverse effect on your carb:


The appearance of the IFR tube in the float bowl casting is deceiving. That little brass “ring” pressed into the upper edge of the bowl is actually a tube that looks like this. The lower (left) end of the tube has the actual IFR restrictor in it. It’s this end of the tube that will get plugged or restricted by sediment and grime, and it cannot be cleaned out by “dipping the carb” in cleaner:


The only way to assure fuel flow through the tubes is to either replace them with correct tubes (which can be difficult), or to “stake” them out by using a piece of wire as a pipe cleaner. The wire must be smaller than the IFR orifice, which means it must be in the mid-twenty-thousands range. You must also know how long the IFR tubes are so you can be assured that your wire is going all the way through the actual metering end of the IFR tubes. Here you can see my wire inserted all the way through a tube:


Noting how much wire is required, the wire is then dropped down through the IFR tube and forced & wiggled through the small orifice end of the tube. It is then dragged up and down through the IFR tube to scrape lose any built-up sediment in the orifice of the IFR. I then flush the IFR with IPA (isopropyl alcohol) from a squeeze bottle, and then blow 120 psi compressed air through the IFR tube to knock any debris out of the tube and the lower fuel well. This cleaning process is essential to any carb that has been in service for a few years, and it will determine the idle quality of the carb and the idle mixture adjustability of the carb:


Here’s another “must-do” item when prepping the float bowl: It is critical that the accelerator pump well have a perfectly smooth inside surface – it must be smoother than a new-born baby’s ***. This is essential for proper life and operation of the accel pump. A surface with any roughness will cause the pump diaphragm to “grab” and seize in the bore after a very short time in service. I use a piece of “grey” ScotchBrite on my little finger, and tediously polish the entire bore inside diameter. Commercially rebuilt carbs that have been media blasted will often have a media-textured surface in the accel pump bore. You may as well throw that carb in the trash can – it has been destroyed:




Retail carb kits usually offer more than one gasket for mating the bowl to the throttle plate, and for mating the airhorn to the bowl. Here we see 2 very similar gaskets:


This is the wrong gasket: The vacuum transfer hole from the port in the side of the carb is partially obstructed. Many carbs will be assembled with the wrong gasket, so do not assume that the gasket you removed is the correct gasket to re-install: Check everything:


This gasket is correct:


Although the carb was not in bad shape, it did have a little surface corrosion, and this hardware looks pretty nasty. We can’t assemble the carb with this:


I little wire wheel work and some processing through one of many available commercial “cold bluing” solutions makes the hardware like new again:


Threaded fasteners, of any kind, should never be assembled dry. Installing clean, dry steel screws into threaded holes in soft zinc die castings is a really bad idea if you want the threads to last. Any threaded fastener should be lightly lubricated to avoid galling, dissimilar metals corrosion, and to assure proper torque:


All threads, including those on the seat and the inlet fitting, are correctly lubricated to prevent any damage to the carb and its threads:


The idle mixture screws are installed into the throttle plate after the throttle plate is attached to the bowl. 4MV carb are given an initial setting of 3 turns out from seated. M4M carbs are set to 6 turns as an initial setting:


The choke pulloff and fast idle system can then be installed to the carb along with the secondary lockout lever:


The choke intermediate lever is fed down into the carb using the intermediate rod. The intermediate shaft can then be easily engaged with the lever as the components mate up:


Successful assembly:


The bowl can now be “populated” with the jets, accel pump checkball & retainer, and the inlet seat:


Always use a correct NitroFill float in a Q-Jet. Never use a brass float – the brass floats are junk, and will fail:


Float level is set by bending the float arm and measuring to the rear edge of the float from the rear bowl wall. A good performance setting is .300”:


Float needle clip is then correctly installed:


It is very common for the power piston spring to have been changed by a “hot rodder.” If you have a stock or near-stock engine, use the correct stock spring. Most stock springs should look like this one. If you believe you do not have the right spring, or you’re not sure, get the right one. Cliff Ruggles has developed perfect reproduction springs and sells them at a fair price:


Make sure the rods are correctly engaged into the jets when you install the power piston. Put your finger on top of the piston and push it down to assure smooth operation:




The kits, as noted, also come with multiple airhorn gaskets. Almost all of them come with a passenger car carb gasket and a truck carb gasket. Note the difference between the two. Truck gasket is on the right:


Correct gasket should fit like this:


Before installing the airhorn, let’s make some checks and adjustments to it, too. First up is the secondary airvalve spring tension adjustment. This is critical to smooth operation of the secondaries upon opening. Loosen the allen-head lock screw about ½ turn. Once loose, the slotted head spring adjustment screw can be loosened and unwound:


Loosen the spring until it disengages from the shaft tang:


Then, tighten it until it JUST touches the tang. Then tighten it ¾ for Chevy’s, or ½ turn on Pontiacs. Snug the allen-head lock screw back down:


During disassembly, we noted that the secondary airvalves were jammed and sticking against the airhorn casting. It’s time to fix that little problem: Carefully loosen the airvalve attach screw by “rocking” them back and forth until they loosen up about ¼ turn. If you just forcefully turn them, they can break. Rock them and humor them loose:


Once they have loosened about ¼ turn, the airvalve can be repositioned slightly on the shaft, moving the airvalve away from any contact with the casting. Here you can see that we have created a gap all around the airvalve to assure that it now operates smoothly and freely. Once repositioned, snug the screws back down:


The airhorn can now be mated to the bowl once the accel pump is dropped into its bore with the return spring underneath it, and the secondary airvalve rod is simultaneously installed into position:


Choke intermediate rod is installed by “fishing” for the hole in the intermediate lever:


…and the secondary rods on their hanger are installed. The rod height is checked by measuring the distance to the rods where they hang from the hanger with the airvalve wide open. Distance from the top of the rear wall of the choke tower to the rods should be .640”. Adjust by bending the hanger arms:


Finally, the accel pump rod and arm are installed. Use a pin punch to align everything before forcing the hinge pin back through the holes:


Now we can check the choke pulloff for operation and adjustment. But first a word about choke pulloffs:

The choke pulloff, in addition to “cracking” the choke open upon engine start, also acts as a “damper” to assure a controlled opening rate of the secondary airvalve. If the secondary airvalve is allowed to instantly “slam” open upon flooring the gas pedal, the car will experience a massive bog and fall on its face. For this reason, a “correct” choke pulloff will have a “bleed” orifice to control its bleed-down rate. Many (if not most) aftermarket choke pulloffs do not have a restrictor orifice, or the orifice is not correctly sized to produce a controlled bleed-off rate of the pulloff. This results in poor, if not impossible, operation of the secondaries. To check your pulloff, simply put a long vacuum hose on it and suck on it. Does it immediately retract? When you release suction, does it immediately and instantly extend? If it does, it is defective, and needs to be modified or replaced. A properly operating pulloff, when you suck on it, should retract at a delayed rate. When you release vacuum, it should take 1 to 2 seconds to fully extend. Using the “instant” pulloff is the same as simply removing the secondary diaphragm spring on a vacuum secondary Holley. Even Holley guys know that does not work well.

So here we’re checking out the pulloff. Vacuum is applied to check the operation of the choke pulloff portion of the system:


The check reveals that the system is opening the choke a little bit too much. The pulloff should open the choke about ¼” as measured from the forward lower edge of the choke plate to the forward inside surface of the choke tower. This pulloff is opening the choke about 3/8”:


On the 1972 – 1974 Q-Jet choke systems, this is adjusted by bending the choke pulloff tang on the linkage. Here we are bending the tang to make it a little longer, thus opening the choke less:


Re-test shows that the adjustment worked, and the choke is now opened ¼” by the pulloff:


The pulloff also holds the secondary airvalve closed when engine vacuum is high. The airvalve rod should be adjusted (bent) so that there is just a tiny little bit of movement (slack) in the airvalve rod linkage when the pulloff is fully retracted. Here I’m testing and feeling to see if the airvalve has any movement at all… it doesn’t. That means that the rod needs to to bent and extended just a tad to provide a tiny bit of “slack”:


Airvalve rod is bent just a little to provide the correct amount of slack in the system. This assures that the “short” airvalve rod is not restricting the pulloff’s retraction travel:


That completes the carb assembly. Here the finished and ready-to-test carb is ready to be mounted on the test engine:




Any “rebuilt” carb must be tested on an actual running engine. There is no way anybody can rebuild a carb and claim it’s set up right if it has not been tested on a running engine – absolutely impossible. Here’s Jay’s carb installed on my 357 small block test mule for a brutal shake-down run:


Engine is up and running with the carb. Cold-start was instant:


The carbs are always fired up with the fast idle screw and the hot idle screw in the as-provided positions when the carb was sent in by the owner. This gives a lot of clues about other problems the engine has with regards to tuning and setup. Here the carb is running cold with the choke closed and cracked open by the pulloff. The fast idle speed, in the as-received condition, was 900 rpm. This is very low for a fast idle speed – it should be up around 1300 rpm. It’s possible that the owner did not like to hear the cold engine “racing” at elevated rpm, and the fast idle may have been intentionally lowered to this out-of-spec setting:


Whatever the reason for the abnormally low fast idle, it was raised to 1270 rpm. This is a good, reliable fast idle speed setting without being too high to drop into gear with an automatic:


Once the engine warmed up, the choke was opened fully, and the fast idle cam dropped down to allow the engine to idle hot. This revealed that the hot idle speed had been set to a whopping 1150 rpm. Such a high rpm setting is an indicator that the carb idle speed is being used to “force” the engine to idle due to other tuning issues. It confirms what we observed with exhaust gas reversion sooting throughout the carb, and retarded timing causing poor engine performance. The extreme hot idle “forced idle” setting on the carb confirms what we assumed and observed about timing and engine tuning. Jay has some timing work to do when he gets the carb back:


The idle speed has now been lowered to a more correct 850 rpm:


The initial idle mixture screw bench setting on the carb was 3 turns out from seated. The wideband showed this to produce a slightly rich mixture at idle, so the screws were turned in 1/2 turn to a setting 2-1/2 turns from seated. This produced perfect idle mixture at 14.6:1. The carb has instant, snappy throttle response, perfectly smooth idle, and instant hot re-start characteristics:



Carb will now be allowed to “hot soak” on the engine and cool down overnight, and then given a cold re-start test in the morning. Once final cold-restart test has been passed, it will be dried out, boxed up, and sent back to Jay so he can have some fun setting up timing and enjoying the car. Let’s hope Jay has some fun with it!!

Lars

Boswell

Thank you Lars! Very thorogh and very informative. Your efforts with photos and explanation are very appreciated!
Kind regards, Norm

lars

Glad you found it useful, Norm! Gotta' pass some of this information on while I still can...

Lars

Roger Dodger

Thank you for this.
It's really too bad (for me, at least) that you @lars don't work on Q-jets from your Northern friends .

In any event, I always enjoy reading your posts and marvel at your knowledge and expertise.

Keep well!

RickDett

I'm glad you didn't rebuild my carb and so many other forum members carbs. If you did I and others would've never have learned ourselves if not for your many technical bulletins and threads. I especially enjoyed this one so detailed with photos and those additional tips.



"A picture is worth a thousand words" to this otherwise complex procedure. They add insight, definition, and clarity to understand what words cannot sometimes describe.



I appreciate the information. Good read.



Rick

73L82AIR

Thanks for taking the time to put this post together. So informative 😎

debueller

Nice work, Lars.

I'm impressed with your knowledge and experience with these carbs.

It's interesting how so many people have a negative opinion of Q-jets.

They are very versatile and I've seen and heard of them doing great at the track, on hard core 4X4's, classics, and on daily drivers.

It's nice to see someone that knows how to work on them and is so willing to share their knowledge.

Thank you so much.

lars

Glad to see you guys still reading and using the info in this thread from a few months ago. Keep those carbs and cars alive!

Lars