fl_799

Hey guys, new to the forum but I've been lurking around for several months

I'm close to picking up a dead stock A4 '89 convertible in the next few days (15K original miles) and I'm already getting my game plan (and parts order) in place. Just want to cover the basics; I'm a wrencher so I'll cover the work myself.

First order of business is a full fluid change (Mobile-1, tranny change, Redline in the D36) and a new fuel filter. Flush the Radiator, bleed the brake lines clean. Might as well cover the PCV valve and grommet too

Since the miles are low, should I be looking at replacing the plugs, cap and rotor or bypass for now? How about vacuum lines?

What really has me concerned is the injector and fuel supply O rings and the fuel pressure regulator. I don't want to go up in flames for a few bucks in O rings and a diaphragm. And replacing the Multitech injectors with the Bosch series 3 22lb/hr injectors seems like a given too while I'm at it.

Am I missing anything else for the first pass? I don't want to put a new (to me) vehicle into service unless everything is up to par considering the car is 24 years old. Your thoughts?


James

leesvet

Good idea, all of them.

You're thinking right.

Fluids, first and always. Change, use quality products, and clean.

Clean as you go. Single MOST important issue on ANY vehicle. Keep the mechanical stuff CLEAN.

Rear end.....change with whatever you can use to suck the grease out. There is NO DRAIN. Be sure to reinstall the posi-lube additive with fresh grease. These rears last forever if maintained.

Fuel system...whew...
Start thinking Pumps and start pricing an upgrade. You MAY need one now, but WILL soon enough. These pumps are fragile, cooled and lubed by fuel. Easy to fry and alcohol fuels do their damage to rubber impellers, then send the trash to the filter.
Pump screen...the 1st to go and the cause of many mystery ailments. New strainer/screen, new pump. Hell with the pulsator.

Filter. I'd change it. Sitting too long...miles TOO low. Trash in fuel or water.

Injectors, regulator. YES. If they are not bad now they will be soon. These were NOT alcohol friendly and they are known to cause problems. FIC has the standard replacement "kit" with gaskets, inj set of late model Bosch-IIIs and O-rings for the rails. IIRC, the kit is still under $300. Best service on the planet too. And DO rebuild the rails. Old O-rings get brittle, and break as you handle the rails to swap injectors......leaks follow.
Car-B-que

Fuel line O-rings at rails. 1 in each steel line fitting.

regulator...the diaphragm is a crap shoot. May or may NOT be bad. best bet is to replace with an adjustable regulator for a little more $ than the stock bladder replacement.

Underside....
I NEVER miss an opportunity to spray off the underside, suspension and all. This car has a bunch of suspension moving parts...all in bushings that make it do what it does, so well. Lube the bushings with SILICONE only and they will last forever. No petro based lubes on rubber bushings....ever. I use pure silicone grease on bushings that I can get into, and wet silicone spray on the rest. I drilled and tapped for grease in certain bushings and keep them nice with the silicone grease...
$hits expensive, so be prepared !

Hubs are sealed, throw away bearing assys...

u-joints...always replace with NON-serviceable joints. Zerks are NOT accessable once installed and the grease holes weaken the joint.

If you got an auto, I like syn tranny fluids. Costly BUT fleet reports confirm a dramatic reduction is trans failures after switching to a synthetic fluid, in fleets that WERE on regular type trans fluids......so that means that ANY trans benefits from the syn fluids, not just the new ones.

brakes...I use a high grade fluid that's compatible with the ABS system of that time...IIRC, the newer synthetics are NOT. Do some research on that before you flush and fill...The ABS is NOT easily repaired and parts for that era can be difficult to locate. Mercedes, Porsche and Audi used this same ABS system in their cars back then. Caddy as well.

Weather strip....if its dry or cracked from age, spend the money on good stuff. Search the threads to get the opinion of the latest DIY weather strip installs.... once in, keep 'em wet with gel or silicone grease. If this is still in good shape, feed it with some gel and watch it soak up the silicone. Armour-all makes a gel that's ok if the grease is not handy. Pool supply stores are rumored to have cheap lube in a tube. For pool seals. Harbor Freight has "Super-Lube"...a small tube, 6oz maybe for $10. IIRC, Graingers sells a full size grease gun tube for some outrageous price.

Learn the normal temps and normal operating "feel". Temps are HIGH. Don't have a cow the 1st time you see 235 degrees...its ok. That's pretty normal in summer with the a/c. 240 is not panic time...The main fan is not designed to come on until 226 degrees...
Buy your FSM ASAP or end up SOL. Priceless in info and diagnostics. About $100. Used sets sold on flea-bay for less.

TPI L98s...watch your warm up time. #7 has a nasty habit of letting the head gasket go in that area...alum heads and iron block? I dunno. Proper warm up helps IMO. Clean coolant is a big plus. Despite what SOME bubba-techs want to think, DEX is good stuff and will prevent corrosion and electrolysis in the cooling system far better, longer than the stock green stuff. A lot of the damage starts in the head gasket edge where the dissimilar metals want to corrode. Just be DAMN sure you flush ALL the green out. This may involve pulling the T-stat to be sure...power flush also. Flush until YOU would drink the water.....then its ok to add dex.
Inside....leather gets leather conditioner, NOT armour-all. Keep dash pad out of the sun when parked...its a $500 chunk of Styrofoam.

I think it cost over $100K to buy a C4 in parts.
That's an expensive $35,000 car. (in 1989)

Can't think of anything else...

of course, all this is JUST my opinion. The FSM has the GM maint schedule and IF you follow it, or do better, this car will outlast you. Its the finest of the GM line from that year. I have one with well over 300K on the clock and still a DD.

Old saying in the equip business....

Grease is cheap !

You get what that means.

Have fun !

BTW
the C4 has some cheap electrical wire in the harness. The insulation tends to dry and crack and break off exposing bare wires that CAN lead to cross signaling and grounding. This causes all known forms of engine performance issues and diagnostic headaches. Be nice to the harness ! Its fragile and it does NOT like degreasers and solvents and soaps under the hood. Use those things gently and carefully around the wire.

ALSO,
The composite transverse (mono-spring) will crack if you get any aluminum wash or brightner even close. The acid in these products instantly breaks down the chemical bond of the resins used in the composite spring and the end result is a cracked/broken spring. Keep the degreasers and acids FAR away from the front and rear spring.

fl_799

I appreciate the great reply my friend.

I ordered everything to handle the fuel rail and the Bosch III 22's a few minutes ago. Probably a good idea to pick up a fuel pump too! I'll add this to the list.

Good point in the U-joints. 4 on the half shafts and 2 on the drive shaft should cover it.

James

Klyde

If your doing U-Joints DennysDriveshaft.com has a nice deal on Spicer Solid U-Joints. They come with new bolts and caps. Get new Teflon coated washers/spacers for the rear axle. Ten bucks maybe. Coat these and the axle splines with never-seize. Helps stop clicking/binding in the rear. The rest of your list sounds good. Throw a new belt in there also. Check tire dates. May look great but could be very old. Do not trust tires over four years old even if they only have one hundred miles on them. These cars use tires to there limits so your life and others on the road around you are on the line here. Continental Extreme Contacts DW are a good choice and cost less then $680.00 for a set of four through TireRack.com. One of the best tires for wet roads. Not that most of us drive in the rain but one day you will get caught in it and they give peace of mind.

If you do injectors get an adjustable pressure regulator and set it for max GM setting for your car. Makes a huge difference. BrakeMotive has a great deal on disc and pads all around if things look rough in that department. Later you may want to replace the rubber suspension bushings with poly. Maintenance stuff first though. While your at it remove some of your power steering fluid and add Lucas Power Steering Fluid/Conditioner. Keeps the old seals from coming apart and protects all the moving parts. Pump and steering rack will last many more years with this stuff.

fl_799

Thanks Klyde. Just book-marked Denny's 'kit'. The Spicers are certainly the way to go. Tires are also on the list since I have yet to date check 'em....current tires are Eagle ZR 40's!

I suppose I'd also get going on preventative stuff inside the car related to electronics i.e. replace the electrolytic caps in the digital dash, bulbs etc and recap the Delco-Bose amps. There is a guy on E-bay selling a later Delco-Bose CD deck with the white on black color scheme and harness for plug and play into '84-'89's. Or I might just solder a line in into the tape head circuit. Don't really want to get sucked into an aftermarket stereo installation but I do like my tunes

James

BOOT77

Anti-seize the axle splines and teflon washers good info!

Churchkey

Good suggestions all.

I'll add: New radiator & heater hoses while the cooling system is open. I would also change the serpentine belt.

Had a 89 vert A4 it was a really good car. Other than normal maintenance about the time it got to 100K miles both headlight doors needed bushings in the motors, one rear radio speaker died & #5 exhaust valve guide failed. After the new set of heads, 2 u-joints & a trans tail shaft seal took it the rest of the way to 135K then I sold it.

carguy604

Mods - Perhaps this thread should be a sticky?! There's some good stuff here... :-)

leesvet

The thing about a 'vette....

all the above stuff that's listed, even the items that other cars don't require, are ALL normal and typical for a Corvette. It may seem a bit extreme to some folks but so is the performance. For people that are incapable of understanding the "why" of all this, I explain it by telling them that you maintain a 'vette like a small plane because your life can very well depend on its performance given what its capable of.
This reinforces the fact that.....

"ya gotta love it"

mxw128

Any reco on where to get the Teflon washers? I had heard that dealer prices are outta sight when they actually have them?

Klyde

I bought my Teflon washers from GMPartsDirect.com. They are for a 96' but might be the same for other years.

Part: 14076924*
Category: Rear Wheel Hub/Knuckle
Description: WASHER
Min.Qty: 1
Unit Price: $4.59
Quantity: 2
Ext.Price: $9.18
Core Charge: $0.00

mxw128

Got it, thanks. I checked the dealer as well and they actually weren't too bad around $6 each. So it'll save on the gmpartsdirect shipping charges. I ended up ordering 4 so I'll have some spares...

mxw128

I'd bet your power steering fluid is probably black, and I'd recommend swapping out all the fluid. I did mine and it made a difference in the steering feel, it's easy to do, you can basically suck everything out of the reservoir fill it with new fluid, start the engine and exercise the rack a few times. Stop the engine and repeat. Do this a few times until the fluid is clear. The last cycle or two id use the Lucas fluid recommended above. There are some threads here that speak to the process as well.

hooked073

sometimes I like to play devils advociate. Suppose the previous owner had the car in a temp controlled room. changed all the fluids once a yr. I would not do a thing untill I knew this information. It would be a shame to change all the fluids that were just changed 2 weeks ago and 20 miles on them. Also Leesvett gives some good info and I am in no way question him. But personal opinion these there is nothing special abouth these things they are you typical SB chevy that is found in millions of cars sense 1956. auto trans that are found in just about every auto car and truck that chev put out in this era. the rear hell everyone from jeep to chev has used. All I am saying is to me they are just cars nothing really special about them till the latter model c5 or some special additions. To me just treat them like you would any other car and youll be fine. Just about anything you want or will need can be found at your local parts store there is rarely a reason to go to a specialty store. I just hate for people to buy a corvette this or a corvette that when in fact there really is no such thing for most of the basics.

NASCAR314

I would suggest simply driving the Vette after purchase, at least on a nice weather day in Virginia. Drive it, enjoy it, and then start figuring out what you NEED to do first, then what you WANT to do. It sounds like a long term commitment, so drive it first, then you will know more about what your repairs accomplish. AND if it's over 50 degree's, drop the top on the vert. and roll with it you gotta enjoy what you bought!

Just BOB

tires? Age? other than that, sounds like youuuuu have a well reasoned approach.

(every fuel pump I have seen has had metal gears. Never seen one with a "rubber" impeller)

fl_799

I can wish that all of this stuff was done but I'm just not that darn lucky on these types of purchases. There is always something.

I guess, for me, doing this type of service work is sort of a religious experience. I get to know the car, form a bond, etc.

James

mxw128

100%

It's therapeutic!!

leesvet

This is likely where the "bond" comes from that non-vette people just cannot comprehend. The intimacy of exploring the various mechanical inner workings of the car lead to building a trust that is the stepping stone to a long term relationship, of any kind.
Can you "bond" to an inanimate object such as a car?
Absolutely ! Me and my car are attached at the hip. Right about where the hip pocket is,...