Engine Replacement?

tbirdfan1993

Registered User
I need some advice. The engine in my 89 SC has 140k on it, fires up, and drives. It idles roughly, but it needs new plugs and wires. My question is about the leaks in the engine... There's leaks coming from the front seal, rear seal, and at least one valve cover. Now the question is should I scrap the engine and spend the $ on a remanned one, or try to salvage this one. Keep in mind this engine has been well lubed up w/ oil even with the leaks, and wasn't driven much in the last year except my purchasing it. What do you guys think?
 
Since you haven't driven it that much the last year, it doesn't sound like your primary mode of transportation. If you are competent, and can do your own work, i think it would be well worh the effort and time to rebuild the motor you have. Or even if you just choose to fix the leaks, a motor with 140K on it probably still has alot of life left in it.
 
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In Addition

Please take into account I am relatively new at the whole car thing, especially with SC's. I don't know much, hell I don't really have a place to work on them. I'm willing to take the time to learn. So again I ask, should I a) replace the whole engine, b) try to rebuild it myself, or c) just fix the leaks. And if you could supply a reason that would be great.
 
I have 190K on my motor and it leaks like mad (I also drive it hard). The only thing I replaced was the valve cover gaskets because when they leak they drip on the exhaust which stinks.

I would recommend using a heavier weight oil like 15w50 Mobil 1 in the summer and a 10w40 in the winter because bearing clearances on high mileage SC's tend to be loose and oil pressure gets low.

I would not replace the engine unless you come across some concrete reasons for doing so. I would replace motor mounts first as broken mounts result in cracked oil pans.
 
I would do a general upper gasket overhaul with the engine left in.

140K is not alot of miles, but these cars generally speaking have weak head gaskets that could probabyl use replacing.

I would pull the heads off, and get them surfaced, and perhaps a valve job.
$250 would be a good ballpark guesstimate for a valve job and surfacing.

The "head gasket set" is about $120 at the part stores. Other areas you will want to look at to make your decision are the head bolts, as stock-type headbolts cannot be re-used, you either need new stock replacements, or ARP head studs. You may also want to look into MLS gaskets, just so you're informed, but on a stockish they're not really necessary; especially with a stock deck finish.

On secod thought, I'd do a "compression test" to be sure the rings are OK before doing this, I believe you can get a compression tester from the free tool rental at autozone... Od another search for compression test to see what is acceptabel and how to do this....

I would also switch to a thicker oil at this age also, some are even using 20-50 on higher mileage, stock engines. You deffinately want to keep after the oil pressure and level in an older engine. Not to mention a thicker oil won;t leak as much... Also, I've had some luck using the "stop leak" or "no leaks" (bars is the name I think) and every few oil changes I add a bottle, and it seems to have stopped/slowed a slow front seal area leak... It was dripping, after using it it, it was still damp just not forming drops under the car...


Another quick note, if you do the HGs, make sure you drain the oil, as not to allow coolant to sit on the bearings, as this is bad... So after you dissasemble the upper engine, drain the oil...

This is assuming now, that you are not building a high end "race motor" and donnot plan on lots of mods, and big boost, etc.

From the sounds of it, you're just wanting to freshen it up a bit...

You need to let us know what your goals are for the car to really be able to say much...
 
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Goals for SC

Well, the first thing you guys need to know is that I am not going for speed or anything major. My goal is to restore the car to a little better than showroom condition. That will eventually include wheels, interior, maybe some exhaust stuff. Not trying to turn it into a racing machine. I want to be able to cruise around, maybe take it to work somedays. Basically a showcar that I can ride in. That's what I want.
 
Like it was posted above spend some time diagnosing the motor. Do a compression test with the motor warm and ECU fuse pulled ( you dont want the injectors spraying fuel) if you run into a low cylinder put some oil in that cylinder if comression goes up its rings if not then its valves. If everything checks out then fix leaks and enjoy driving the cars. These motors are on the expensive side to rebuild.
 
Anymore Suggestions?

I'm going to change the oil in my car and use 20-50 (couldn't find 15-50, so f**k it), and try STP stop leak to slow down my leak. Anyone else got a suggestion?
 
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