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Discussion Starter #1
I have a GM 350 290hp crate motor with around 700 miles and it smokes real bad. It didn't start smoking until around 150 miles than started a little and got worse. Ever since it got worse. I have an appointment monday with the dealer I bought it from. Did they fix your problem and take care of you with your problem?

Some things...
- Blue smoke.
- Good intake gasket, changed it already.
- Not sucking PCV into carb.
- Not sucking Trans into carb.
- Not loosing rad fluid.
- OIL ON SPARK PLUG THREADS, Plugs look tan. Could be because of MSD ignition.
 

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Do a search here in T/chevelle titled " FRANKINCRATE" for all the GM crate motor info/issues you will need,same exact issue your having is covered though the cause of your smoking/oil use may be different then his was.

Scott
 

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opps,sorry for the miss spelling.

I cant see any reason why the GM sbc couldnt have the same reason for oil burning issues like you had with the bbc which was if i remember correctly low tension oil rings with cyl honing not being done with torque plates at factory but please correct me i am wrong on that one.

Scott
 

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A new GM crate motor should not smoke. I sounds like either the rings did not seat or the valve guides are bad. Blue smoke usually means that it is burning a lot of oil.

Don't wait too long before dealing the GM about this. The warranty period is short if you install the engine yourself instead of having a GM approved shop do the installation.
 

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It should not smoke if used as it was intended to be used. A lot of the magazines have shown how these engines can be hopped up to make a lot of power; but they were never intended to be used that way. That being said, if it is just a replacement for the engine in your 77 Burb. then you should consult your dealer. 700 miles should have fully seated the rings unless it was idling back and forth the the store or 650 of the 700 miles with a 250h.p. shot of nitrous. Thes things aside I can not 100%speak for this model; but if it is regulated like the higher performance engines offered by the General and made in the U.S.A., I can guarntee that you would be hard pressed to find a local shop with as many quality systems in place, latest machines, and tests done to ensure that you get a quality product that lasts. It is a world that most people are amazed with and the magazines do not cover. Do not get me wrong, just like everything else sometimes "stuff happens" this is why you need to make sure that you have your facts ready when you approach your dealer. In the end it will be between you and him reguardless of what is said here.
 

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Have you tried to call the GM Powertrain Contact Center? This is set up to assist on problems with their product. 1-866-453-4123 This is an 8 to 5 hotline. You may have to negotiate a few phone prompts, but will get to a GM certified tech. They may still require you to take it to a GM dealer, but you may have a little more piece of mind in talking to their Tech Center. :thumbsup:
Frank G.
 

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Discussion Starter #9
Have you tried to call the GM Powertrain Contact Center? This is set up to assist on problems with their product. 1-866-453-4123 This is an 8 to 5 hotline. You may have to negotiate a few phone prompts, but will get to a GM certified tech. They may still require you to take it to a GM dealer, but you may have a little more piece of mind in talking to their Tech Center. :thumbsup:
Frank G.

Thanks alot. I called the number and told him the whole story. He did tell me to go to a dealer, but he also gave me a case number. Told me to give them the case number and have them call him if they had any questions. I guess the more info the better. I'll give them all my oil reciepts and whatever else I have and hope for the best.
 

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MNM99 Glad to hear that worked for you. GM is usually pretty good with their tech help and warranty.
Frank G.:yes:
 

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mmm, (Name ?????????)

One of my customers with the same exact engine is having smoking problems. He took it to the dealer and the resealed the intake, but he still has problems. Brought it by the shop the other day and it seemed to be running pretty rich to me. This will affect the rings and cause smoke. Told him to "clean up" the carb and see what happens. He has another identical engine in another vehicle with no problems at all.
 

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Search "GMPP 454 HO sucking oil"

This is my engine---I had it nearly 18mo before firing it
A 2600 miles it is out of the car and at a machine shop:mad:

GM Powertrain Center and the GM Customer Service were absolutely useless to me.

They both claimed that since I bought and intalled the engine myself-----it was all on me.

Vince posted some pics of his issues and also posted a link to his thread.

Pretty good read-----although-----these are way different engines, his and mine.

Back in the 80s I bought a L-82 Crate 350, to put in one of my pick-ups.
in 180,000 miles-----never used a quart between changes.
(probably never should have sold that motor)
The 454 in that truck now has about 150,000----maybe 2qts in 5000mi
These are all hard trailer towing miles too.

Kinda sad GM can't build one now to give us at least 500mi qt.

(97 t-bird 4.6>>>>>3000 to the qt>>>>>190,000 mi)
 

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I work at a dealer in Ca. We had 3 290hp 350 crate engines that smoked and burned oil.
After resealing intakes and other diagnosis we found that the valve spring retainers were smashing the valve seals, not enough clearance with the 290hp cam, I think the lift is like .390.
We sent the heads to a machine shop, they said they had to remove .100 off of the top of the guids to get the proper clearance. replaced seals and reassembled. never seen any of them back.
I may be able to find info on cases from our shop if you need.
Bret...
 

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Discussion Starter #14 (Edited)
mmm, (Name ?????????)

One of my customers with the same exact engine is having smoking problems. He took it to the dealer and the resealed the intake, but he still has problems. Brought it by the shop the other day and it seemed to be running pretty rich to me. This will affect the rings and cause smoke. Told him to "clean up" the carb and see what happens. He has another identical engine in another vehicle with no problems at all.

I thought rich or intake in the beginning. I replaced the intake gasket last week again to make sure and I didn't see any signs of leaks. I also bought a Innovative air fuel meter for around $450 and did some testing www.innovativemotorsports.com . I'm running around 12.5 at idle and a nice steady 13.5 cruise. My 1500-4200 rpm log shows a nice slope from 12.6 to 12.0. I know I'm A LITTLE rich but with these logs It isn't rich enough to cause smoke or wipe out the rings. I have a holley 670 avenger and a holley 600 stock and got around the same A/F readings from both.
The last time I went to the dealer at around 50 miles for a miss he adjusted the carb and recommended going to this carb place near me and getting a Qjet carb. I went to the carb place as he recommended and they said theres nothing wrong with yours. They ended up doing some work to the idle circuit that make it idle better. GM states in there parts to use a Avenger 670 carb with this motor, so thats what I did. He also disconnected my vac advance before I left, but thats another story.
Do you think he can say the carb did it since I didn't go out and buy a Qjet?

Marc....
 

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Discussion Starter #15 (Edited)
I work at a dealer in Ca. We had 3 290hp 350 crate engines that smoked and burned oil.
After resealing intakes and other diagnosis we found that the valve spring retainers were smashing the valve seals, not enough clearance with the 290hp cam, I think the lift is like .390.
We sent the heads to a machine shop, they said they had to remove .100 off of the top of the guids to get the proper clearance. replaced seals and reassembled. never seen any of them back.
I may be able to find info on cases from our shop if you need.
Bret...
That would be great. Any info I can get would help. I just don't want them saying it's something I did. I made sure I did everything right because of everything I went through with MY last motor.

Marc
 

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Discussion Starter #16
Search "GMPP 454 HO sucking oil"

This is my engine---I had it nearly 18mo before firing it
A 2600 miles it is out of the car and at a machine shop:mad:

GM Powertrain Center and the GM Customer Service were absolutely useless to me.

They both claimed that since I bought and intalled the engine myself-----it was all on me.

Vince posted some pics of his issues and also posted a link to his thread.

Pretty good read-----although-----these are way different engines, his and mine.

Back in the 80s I bought a L-82 Crate 350, to put in one of my pick-ups.
in 180,000 miles-----never used a quart between changes.
(probably never should have sold that motor)
The 454 in that truck now has about 150,000----maybe 2qts in 5000mi
These are all hard trailer towing miles too.

Kinda sad GM can't build one now to give us at least 500mi qt.

(97 t-bird 4.6>>>>>3000 to the qt>>>>>190,000 mi)
I read that whole post. That really sucks. They better not say it's my problem. I went by the book and did everything that GM states. They saw the motor at around 60 miles for a miss. After I left and got home it was idleing in my driveway and thats when I started to see smoke. I called them right away to let them know and also at 300 and 500 miles. Now it's 650 and I'm bringing it in again. So they know my deal.
When they did have it He must have let it idle for a good 45 min with 60 miles on it. Maybe the cylinders glazed? I don't know.
 

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Same problem. Everyone I asked said it just needs to break in. I've never had this problem with other engines. 290 h 350. Smoked from the beginning. Still smoking after 1700 miles. Up in Canada the car has to pass an air test to be insured so it's a major pain. Did a compression test - around 115 dry - 130 wet. So is it a waste of time to change the valve seals? Will they just get smashed?
 

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Discussion Starter #18
Same problem. Everyone I asked said it just needs to break in. I've never had this problem with other engines. 290 h 350. Smoked from the beginning. Still smoking after 1700 miles. Up in Canada the car has to pass an air test to be insured so it's a major pain. Did a compression test - around 115 dry - 130 wet. So is it a waste of time to change the valve seals? Will they just get smashed?

I'm with you. My brother-in-law just had a 408 stroker built at around 600 hp and doesn't smoke a bit. I go to car shows every tuesday near me and run into alot of people that have crate motors. Every one of them say there great, never had a problem. I would give a couple of hundred miles for a little of smoke but thats it. I'm at 700 your at 1700 , they shouldn't smoke! If your seals are bad, what caused it? Thats what you have to think about. Like the other person said his were getting crushed and had to cut the guides. I'm more worried about leaving my car at the dealer and them working on it!!
 

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Hey mnm99, i couldnt find any info , the last one was a few months ago, We only made a case on the first one due to difficult diagnosis. Now that we know what the problem is we just fix them as needed.
The easies wy to tell if the seals are the problem is to remove the valve covers and check for parts of the seals, most of them had orange colored seals and you would find small orange particles in the lower head area and at the end bolts below the oil drain holes. We even found the small spring from one of the seals on one of them. Or you can remove some of the springs and physically check also.
Just replacing the seals wont fix the problem. The problem is that the valve guids are too tall and need to be cut down. I beleive that these engine were assembled in mexico. They use these same heads on the standrard replacement 350, but they have a smaller cam so they dont have this problem.
 

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Discussion Starter #20
Hey mnm99, i couldnt find any info , the last one was a few months ago, We only made a case on the first one due to difficult diagnosis. Now that we know what the problem is we just fix them as needed.
The easies wy to tell if the seals are the problem is to remove the valve covers and check for parts of the seals, most of them had orange colored seals and you would find small orange particles in the lower head area and at the end bolts below the oil drain holes. We even found the small spring from one of the seals on one of them. Or you can remove some of the springs and physically check also.
Just replacing the seals wont fix the problem. The problem is that the valve guids are too tall and need to be cut down. I beleive that these engine were assembled in mexico. They use these same heads on the standrard replacement 350, but they have a smaller cam so they dont have this problem.

Thanks I'll take a look tonight.
 
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