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-   -   Seeking advice - rebuilt engine failed within 1,000 miles (https://67-72chevytrucks.com/vboard/showthread.php?t=731150)

skizzik 02-23-2017 05:07 PM

Seeking advice - rebuilt engine failed within 1,000 miles
 
Hi everyone,

I could use some advice about what action to take and how much it would cost. Does it sound like I need another head gasket already, or is this engine block bad?

I have an 89 Suburban with a standard 350 5.7L V8 TBI engine. I had the engine completely rebuilt in April 2015 because the head gasket was at a point that it needed to be repaired (I overheated and it had been burning coolant out the tailpipe badly for 2 days prior), and it had been burning oil and I was tired of topping it off. The mechanic replaced the water pump and radiator too.

After the rebuild, it drove like butter. It was amazing. But the temperature gauge occasionally would show the engine overheating and then it would usually drop back down to operating temperature within 20 min. I told the mechanic and he replaced the temperature sensor. It continued to act the same way, but the mechanic didn't think anything was wrong. I heard a small amount of gurgling in the coolant backup tank once. Otherwise, no obvious signs of definite overheating.

Fast forward to this past November. The suburban isn't my primary vehicle, and I used it on average every 2 months and kept the battery hooked up to a trickle charger most of the time. I only put about 1,300 miles on the engine since the rebuild. I used the Suburban to pick up a Christmas tree and had no problems. I checked the fluids before leaving and they were all fine. The next day, I tried driving the Suburban to work and it overheated within 15 minutes and left me on the side of the road. I had it towed to a local shop and the mechanic said the head gasket needs replacing and the engine won't even start. The truck is unusable. When I explained the recent rebuild, he said he suspected the engine was bad and needed replacing (cracked block maybe?).

I have been trying to contact the mechanic who did the rebuild, but he is ignoring me. He was a guy at the edge of town who speaks little English and I received no written warranty of any kind.

What would you all do here? Is it likely that it just needs another head gasket, or does it sound like this engine is unfixable? How can I determine this? Thanks.

Palf70Step 02-23-2017 08:11 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
I would say regardless of the mileage on the engine, most don't warranty past a year. It could be head gasket like you mentioned or the rear intake manifold gaskets that tend to link depending on the intake gaskets they used, especially if it sits a lot with dexicool as the antifreeze.

skizzik 02-23-2017 08:53 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by Palf70Step (Post 7867717)
I would say regardless of the mileage on the engine, most don't warranty past a year. It could be head gasket like you mentioned or the rear intake manifold gaskets that tend to link depending on the intake gaskets they used, especially if it sits a lot with dexicool as the antifreeze.

Thanks, Bill. Sounds like you think it's fixable.

Kim57 02-24-2017 08:57 AM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
You should do a compression check. That should show where the problem is.
It's possible the head was warped from over heating the engine and then it will never be right until surfaced. That could have been the problem with the overheating after the rebuild.
Kim

b454rat 02-24-2017 10:37 AM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Check the thermostat?

skizzik 02-24-2017 11:59 AM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by Kim57 (Post 7868101)
You should do a compression check. That should show where the problem is.
It's possible the head was warped from over heating the engine and then it will never be right until surfaced. That could have been the problem with the overheating after the rebuild.
Kim

Thanks Kim. I had a mechanic do a compression test, and he said it failed and indicated the head gasket had failed.

skizzik 02-24-2017 12:00 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by b454rat (Post 7868171)
Check the thermostat?

Haven't checked the thermostat. Worth checking I guess. I thought most modern ones failed open though?

Palf70Step 02-24-2017 01:34 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by skizzik (Post 7868240)
Haven't checked the thermostat. Worth checking I guess. I thought most modern ones failed open though?

No, unless you ask for one, many/most are still traditional style. Hope it is not too bad on your engine and maybe a good clean up and new gaskets will take care of it.

Tom 02-24-2017 05:54 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Define rebuilt. Decked the block, heads, line hone the mains, new bolts and re-sized rods, new/rebuilt crank etc......or as most people think just a hone with new rings, bearings and gaskets?

skizzik 02-26-2017 03:16 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by Tom (Post 7868532)
Define rebuilt. Decked the block, heads, line hone the mains, new bolts and re-sized rods, new/rebuilt crank etc......or as most people think just a hone with new rings, bearings and gaskets?

I don't know. I was told that every replaceable part would be replaced. It took him like 4-6 weeks to complete.

skizzik 02-26-2017 03:17 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
I'll check the thermostat and post the results. I'm gonna be so pissed if that caused the problem...

skizzik 02-28-2017 04:32 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by skizzik (Post 7870260)
I'll check the thermostat and post the results. I'm gonna be so pissed if that caused the problem...

I tested the thermostat and it seems fine. Physically it looks fine, and it opened in boiling water and closed in closed water pretty quickly.

Anyone else know what could cause a recently rebuilt engine to overheat and need a new head gasket if the coolant level, oil level, and thermostat were fine?

Mr_Rich 02-28-2017 05:09 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
When you have a failure so early I'd suspect the work that was done on this engine and I wouldn't trust it or the "mechanic" who built it. BTDT, and it was with a mechanic at a Chevy dealership 25+ years ago. After my experience I found it easier to buy a 350 crate engine at a local Pontiac dealer and installed it myself on the street outside my apt. at the time. That engine was still running strong for twenty years until I swapped it out for my spare that had fresh seals and lower miles as one of my retirement projects. Were any shortcuts taken and less care or time taken reassembling this long block? Probably a teardown and inspection will tell the tale. It could be a cracked block and 1000 miles isn't enough to reveal some of the damage yet other than the overheating. My factory 305 in '89 had a cracked block which led to my troubles at the time.

Tom 03-01-2017 05:44 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by skizzik (Post 7867580)
I have been trying to contact the mechanic who did the rebuild, but he is ignoring me. He was a guy at the edge of town who speaks little English and I received no written warranty of any kind.

Combine this with not knowing any actual machine work done only that "every part is replaced" worries the crap out of me. Did this cost you $2,000+ to rebuild? Cause that's the going rate when having someone else do the disassembly and re-assembly of the engine itself not counting install into the truck.

You know the head gaskets are done. Pull the engine and get it checked over before going any further. Find a real shop not an edge of town barely speaks english no reciepts or warranty guy living in a tent.

skizzik 03-03-2017 07:58 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by Tom (Post 7873674)
Combine this with not knowing any actual machine work done only that "every part is replaced" worries the crap out of me. Did this cost you $2,000+ to rebuild? Cause that's the going rate when having someone else do the disassembly and re-assembly of the engine itself not counting install into the truck.

You know the head gaskets are done. Pull the engine and get it checked over before going any further. Find a real shop not an edge of town barely speaks english no reciepts or warranty guy living in a tent.

I spent $1,200 for a "rebuild", radiator, and R12 recharge. It might've been $1,500, but I'm pretty sure it was $1,200. The mechanic has a lot full of old cars, and a couple shop buildings. He's a mechanic for a living who's been doing this for decades and I thought was trustworthy, but I do suspect something faulty with his work.

I had a different mechanic look at it today. It took a little bit to start (I think because of lack of compression), but it did start and sounded fine to the both of us. There was white smoke coming out of the tailpipe along with some liquid. It rain for about 15 seconds and then I started seeing the coolant reservoir tank rapidly bubbling and we shut off the engine. I tried a few hours later to start it and couldn't (maybe there's water in the cylinders now).

He suggested getting a new engine or at least a new short block (bottom half) and having him put it in. The maintenance guy who works at my apartment suggested that I learn how to replace the head gaskets myself (he learned himself on his old truck), but that seems like quite an undertaking.

billnorman 03-04-2017 07:47 AM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Lots of bubbles in the coolant sounds like a headgasket or cracked head or block. Water in the tailpipe is normal when first started but not after it has been running for a while. Check the oil, if it's creamy, you have a real problem. I'm not sure, but if your intake manifold leaks you could also get water inside the cylinders. If a compression test shows low one one or two ajacent cylinders you probably need a head gasket and need the heads checked for warping.

skizzik 03-04-2017 12:34 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by billnorman (Post 7875955)
Lots of bubbles in the coolant sounds like a headgasket or cracked head or block. Water in the tailpipe is normal when first started but not after it has been running for a while. Check the oil, if it's creamy, you have a real problem. I'm not sure, but if your intake manifold leaks you could also get water inside the cylinders. If a compression test shows low one one or two ajacent cylinders you probably need a head gasket and need the heads checked for warping.

How can I tell if it's a cracked head or block? I'd hate to fix the head gasket(s) only to find out later that there's a crack.

Mr_Rich 03-04-2017 01:35 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by skizzik (Post 7875586)

He suggested getting a new engine or at least a new short block (bottom half) and having him put it in. The maintenance guy who works at my apartment suggested that I learn how to replace the head gaskets myself (he learned himself on his old truck), but that seems like quite an undertaking.


Noooooo.... At this point the upper half of the engine is damaged. Buy a crate engine for a fresh install. You're just asking for trouble (again) if you try to put the old heads on a new short block. Like I said before...BTDT.

skizzik 03-04-2017 07:46 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by Mr_Rich (Post 7876191)
Noooooo.... At this point the upper half of the engine is damaged. Buy a crate engine for a fresh install. You're just asking for trouble (again) if you try to put the old heads on a new short block. Like I said before...BTDT.

Good point. The bottom may be good, but we know the top isn't. Not sure why he suggested that, or why I thought it made sense at the time.

A crate engine is like $2,000. Is there anything I can do in the range of like $500, or is a crate engine really what you'd recommend?

Kim57 03-04-2017 08:53 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
I would pull the heads to see what's going on. A compression test should show which cylinders to be concerned with.
Look for obvious damage to start with.
You can check for a warped head by putting a straight edge on it with a strip of paper under it and seeing if it slides out. Some cracks need to be found by having it magnafluxed.
Hope you find the problem.
Kim

Kim57 03-04-2017 08:56 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
It's also possible the original mechanic didn't torque the heads properly which would cause problems.
Easy to see if any bolts are loose.
Kim

billnorman 03-05-2017 06:11 AM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Quote:

Originally Posted by Kim57 (Post 7876510)
It's also possible the original mechanic didn't torque the heads properly which would cause problems.
Easy to see if any bolts are loose.
Kim

That's why a good mechanic would remove the head bolts by hand with a ratchet rather than an impact wrench. The rattle wrench is faster but doesn't tell you much.

speedygonzales 03-05-2017 01:36 PM

Uh not quite
 
Quote:

Originally Posted by skizzik (Post 7868237)
Thanks Kim. I had a mechanic do a compression test, and he said it failed and indicated the head gasket had failed.

Has anyone looked at the quality of the oil and see if it at least looks like a milkshake????? Has anyone looked at the plugs to see what they indicate? Coolant would be real noticeable on the plug.

A compression test will indicate there is low compression only. It can not point to the cause. In most cases a low compression test is related to bad valves. I don't think this case is like that however.

He's making an assumption that because it's over heating and there is 1 or more cylinders with low compression, the 2 must be related. Not the best way to trouble shoot but it allows him to make an opinion without charging.

What should have been done was a leak down test. Also a chemical check of the coolant to see if it has combustion gases in it. IF the leakdown test produces bubbles in the coolant, no need for a test of the coolant.

At this point the head on the side in question should be pulled to see if it is indeed just a gasket or something mores serious like a crack. At that point the quality of the cylinder walls can be evaluated.

A clear understanding of a test to confirm or deny a suspected problem will be very helpful. Go where the test indicates and understand EXACTLY what each test will show or in this case, not show.

FWIW I'm putting my money on a cheap (went bad) head gasket.

docrock 03-08-2017 01:13 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
This is a great post about awareness of what your "rebuilder" is doing to your engine. Some rebuilders will buy a rebuild kit for 300 on ebay and call it done. Sure you may have new rings, bearings, and gaskets, but if you didn't have the block and heads magnifluxed you threw money away. Radiators are cheap and I would have changed that when I did the motor. I blew a lot of head gaskets not changing that. On these motors after 86 the heads crack easily, when they overheat. My 93 blew the intake gasket. When I removed the intake there was a lot of corrosion that had to be addressed or it would have leaked again. A good machine shop is your best friend, especially if they let you check in with them as they progress through the process. Crate engines have gotten very inexpensive and I might go that route on the next project. But if you don't fix the cause you will blow the new motor

skizzik 03-10-2017 12:20 PM

Re: Seeking advice - rebuilt engine failed within 1,000 miles
 
Ended up having the heads taken off and found head gaskets that looked like they hadn't been replaced during the rebuild, along with a crack in one of the heads, and a crack in the new radiator from when it overheated. So put in a couple of new rebuilt heads, head gaskets, intake gaskets, and radiator, and drove it a little yesterday to try it out. There was quite a bit of white smoke that I'm hoping just needed to burn off, because it went away after a while.

More testing needed with the engine but so far so good. The temperature gauge on my dash suddenly no longer works, though. Strange.


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