engine rebuild or replace

[Michael]

I have a July 1991 w/156,***. She burns at least a quart every 1000 miles. What I would like to know is should I rebuild her or replace her. It seems that it would be cheaper to find one with less mileage than to rebuild. I don't see any oil around the engine or on the bottom. It appears to be internal, but I am no expert. it ahs never had any of the 60k done to her, but she does feel amazingly strong. Thanks ahead of time for your input.

 

[clintonk]

Are you certain you're not leaking oil? Leaks from the front main or cam seals often burn off on the exhaust. Do you ever see any smoke rising from around the hood? Any smoke out the back on startup? I'd check those things, then run compression/leakdown tests to check the condition of the internals. And a quart in 1000 miles isn't awful if there's no oil on the garage floor; a few quarts of oil is much cheaper than a rebuild or replacement.

Clinton Knight
'90 White 183K
'95 Green 53K

 

[Blast7]

I would not do anything. My SHO uses up a quart of oil every 3K miles. I am leaking some oil from the front crank seal and the oil sender.

 

[speedy91]

I would defiantly replace your engine with a junkyard one. Either a 3.0L swap (easiest) or upgrade to a 3.2L, which is more complicated. That way you get a factory built motor for a fourth the cost of rebuilding your current motor. Another point, my boss tried to find someone to rebuild a SHO 3.2L and could not find anyone that would touch it.
Eric

 

[projectSHO89]

Oil is cheap compared to a new engine.

For about $200, you can keep the car running for another 150K miles at your current rate of consumption.

FWIW, that is acceptable consumption for any NEW car's engine.

Steve
89

 

[Michael]

How do you run the compression test/ leakdown test. If you don't mind me asking. My goal is for this baby to scream. So if I am lossing compression than I am losing HP. Thanks for input.

 

[YodaSHO]

My SHO uses a quart or so every 1k miles as well. It's very strong though. I know where it's leaking from as well.

Your car is leaking oil through the valve cover gaskets around the spark plugs. Take a paper towel, roll it up and stick it down your spark plug holes. You'll probably get some oil residue on it where the oil's leaking down that way.

It's a little work to fix it. You have to take off the plenum and valve covers, get new gaskets and replace them all. However, I've heard of people using silicon (Ultra Blue) down in the holes and supposedly have stopped the leaks or slowed them down significantly. Some people take out the seals and soak them in gas or oil. This makes them expand again and seal...sometimes. I would buy new one if you're going to go through the trouble of taking the valve covers off though. Just my 2 cents.

 

[luigisho]

That's a bold statement considering there was no mention of misfires or loss of power. Have you noticed any leaks on the ground or change in exhaust color? Burnt oil smell? Mine leaks about that much from the rear main seal. It'll stay that way until it gets alot worse or when it needs clutch work.

 

[Michael]

there is very little oil in the #4 and #5 plug wells. Not enough to make me jump right on in and replace the gaskets. No visible oil on the floor either.?

 

[luigisho]

Apparently Yoda was using the force and nailed the oil in the wells diagnosis. How about that?

You will eventually have to do it anyway. I can't see your profile as I type but for most of the country: why not do it while it's warm outside? These are the heads and will have to be done unless you buy a longblock. Even then, if it's been sitting for a while, it would be a good idea to do gaskets on that also.