BeaterShark

Well, after burning 1 qt every 600 miles, I decided to pull the engine. This is 3 years and 30k miles after I put it in. Over that time, I've gone through great pains to find the reason for the oil burning, but could not, so I decided to just pull it.

This is not for the faint at heart.

Anyway, here are the pics:

Driver's Side

Passenger's Side

I really don't understand the #3 buildup. Also the exhaust valve was paper-white. I'm pretty sure it was still sealing (was going to do a leakdown but was having problems with my compressor) and overall the engine still ran good. I wonder how much pre-ignition I was getting with those glow plugs sitting on the pistons.

The plan is to go over everything with a fine tooth comb, put in some new rings and bring it to life again. I havn't opened up the bottem end yet, but will turn the crank and put in new bearings if needed. The cylinders do not appear to have any wear.

Anybody have any suggestions for cleaning up the garbage on the pistons?


[Modified by BeaterShark, 5:04 PM 7/6/2004]

73'Vette

Hmm, no pictures....
Although I can't help with your engine problem, I can help you by linking your pictures for you.

DRIVER'S SIDE:
http://users4.ev1.net/~theamys/vette...rvrPistons.jpg

PASSENGER SIDE:
http://users4.ev1.net/~theamys/vette...assPistons.jpg


There ya go! Good Luck!


[Modified by 73'Vette, 4:48 PM 7/6/2004]

BSeery

I don't think the forum likes the "~" in the link to the pictures.

73'Vette

Yeah, it doesn't like something. Oh well, I modified my message to include links instead of images.

MotorHead

What was the compression ratio and did you notice any pinging ?

I still do not see where your oil was going did the valves have oil caked on them ?

GrandSportC3

What type of oil did you run? What brand of gasoline??

BTW - on all the C3's that I've owned.. I've never consumed much less oil than 1 qt/600 miles and I had 2 brand new engines.. That's not too bad at all...


[Modified by GrandSportC3, 8:17 PM 7/6/2004]

dman535

My motor has been in my car for11 years/ 60,000 miles - numerous cam changes. been to 7000 rpm, towed a trailer from Detroit to Nashville and back. I go through maybe a quart every 3000 miles.

GrandSportC3

MotorHead

The way I burnt oil in my last motor I didn't need to do oil changes

GrandSportC3

I personally don't care too much about oil consumption as long as the engine runs good and strong and doesn't smoke..
Oil aint that expensvie...


[Modified by GrandSportC3, 10:01 PM 7/6/2004]

LAvetteman

I have a question. Who is Amy?

yellow 72

I thought that was the reason you went to a crankcase evacuation system, in order to keep the intake charge free of oil contamination and allow you to make "more power" and reduce the risk of detonation.
Well if it 'ain't leaking it it's burning it

Chris, when you pull it apart make sure the rings were installed right side up...and at the very least borrow or rent a bore guage and make certain those cylinders are Round.....


[Modified by yellow 72, 10:43 PM 7/6/2004]

BeaterShark

At first, I ran 15w50 Mobil1. After I realized I had an oil burner, I switched to conventional. Mostly ran Chevron straight 40/30 (summer/winter) mixed in with some 20w50. I was trying to keep an oil with a low ash content since I knew I was burning the oil. Now, I'd run Motorcraft 15w40 as it has alot of zinc and other good HDMO stuff and still a low ash (.9). Suprisingly, the Mobil1 oils have a 1.5 ash just like most HDMOs (Delo, Delvac, etc).

Have you ever pulled those engine apart?

My engine ran good and it didn't smoke. The only smoke I ever got was black during WOT at about 5500+ RPM. It's not the price of oil that bothered me. It was my fear (confirmed) that I had a bunch of junk on the pistons that was probably hurting performance and possibly pinging (although I couldn't tell) which would lead to the death of my engine.

BeaterShark

Being from south central LA, you might be able to figure out who Amy is. In fact, if you know any other Amys, I probably know them as well.

Mr.Gearhead

"I really don't understand the #3 buildup. Also the exhaust valve was paper-white."

I had this same issue with my... ummmm 1988 Mustang GT. (many moons ago). I had a Paxton Supercharger on it to keep up with all the Vettes.. hee hee. ALL my valves were white. I found that the valve guide were experiencing blow by and the carbon was building up on the pistons due to the oil getting in the combustion chamber. Metal conducts heat much better when it is clean. Your piston looks like it has seen better days. I am sure the carbon on that piston has contributed to the heat build up in that cylinder. This will definately cause early detonation.

You could do a leak down test or... just pull that valve and look for carbon build up on the underside of the valve. The valve was probably sticking if it has a lot of carbon on it. You may only need new guides. Worst case.... new valves and guides.

oh.. forgot to add. Soak the pistons in gas. Then wire wheel them... good as new!


[Modified by Mr.Gearhead, 12:54 PM 7/7/2004]

70BBvert

Had a similar problem with my 68 Mustang also. Went through a Qt every 100 miles. After 2 rebuilds of the heads & new seals, I pulled the motor & changed machine shops. My engine looked like this:







Turned out the valve guides were shot due to the tapered valve stems. They were out by .003" and according to the machine shop, they probably destroyed the guides shortly after the initial startup.

Ever since that rebuild, I use 1/2 a Qt in 3500 miles. BY the way, the pistons were glass beaded and re-used. They looked brand new.

Good luck

Jim


[Modified by 70BBvert, 12:03 PM 7/7/2004]

GrandSportC3

Well - my car was smoking at idle with the PCV system hooked up and I was buring 1 quart every 200 miles.. After installing the evacuation system - the oil consumption went down to 1 quart every 600 - 700 miles depending on how I'm driving.. I'm hardly burning any oil.. but the evacuation system sucks unburned oil out of the exhaust (by design).. So - instead of burning 1 quart every 200 miles - I'm now sucking 1 quart every 600 miles out of the exhaust.. I rather lose my oil unburned rather than burning it and fouling the plugs.. The main problem is that radical stroker engines build up a lot of pressure which also causes flattering of the rings and therefore oil gets past them... A PCV system has high evacuation at idle because of high vacuum at idle.. but has no vacuum at WOT.. However - WOT is the time that most pressure builds up... At WOT - the PCV system doesn't have any vacuum to evacuate the pressure - the pressure gets past the rings and gaskets and causes oil leaks.. Well - that's at least the way that I understand it but I could be wrong.. The only thing that I know for a fact was that the smoking and major oil consumption stopped after I installed the Crankcase evacuation system!

GrandSportC3

Nope.. They ran fine.. Looking back.. I should've installed crankcase evacuation systems on those engines... I'm sure that my oil consumption was pressure related.. I spoke with several people at local Drag Strips and I was told that you need more than a PCV system to evacuate the pressure on a radical engine.. A regular - close to stock 350 small block won't build up that much pressure and a PCV system will work just fine for evacuation.. but a radical stroker engine needs more than that..
I've never had any issues with performance on any of my engines.... At my current engine - I know that I'm losing about 1 quart/600 miles by design. At high RPM - there's very high vacuum building up in the exhaust and it sucks unburned oil out of the exhaust through the evacuation system... I would be concerned if I would be burning the oil.. but as long as it's going out the exhaust unburned - it's ok with me!!

BSeery

Back in the early '90's a GM mechanic showed me the best stuff for cleaning pistons and valves like that. He said GM had come out with this new "stuff" in a can and it was a fuel system cleaner / engine cleaner. He showed me a piston that was just about as nasty as yours in the picture above. He poured the engine cleaner in a coffee can and set the piston in there. He pulled a piston out that had been soaking for about 15 minutes and used a red rag to literally wipe the top of the piston clean !!! I was truely amazed at how well a chemical could remove all that carbon.
I looked at the can he handed me and the ingredient in it was something called "Techron".
Well, years later Chevron, who makes Techron, now puts the stuff in their gasoline and in some stores you can find it as a fuel system treatment. They have 2 "strengths". One is a fuel system treatement and the other is called an engine cleaner (more concentrated). Both versions you pour in your tank and drive.
You could try to get some of that stuff and try to clean the pistons, or try and go to GM and see if they still carry the high strength version in their parts department.

GrandSportC3

I mostly use Chevron gas.. so I get a lot of techron in my engine