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Discussion Starter · #1 ·
Having a bit of a problem with oil burning. Put a 408 stroker kit on a 351C engine. Ever since installation of kit it has been burning oil. Ring gaps were staggered during install. Valve stem seals have been replaced Guides looked good and the heads were done about 2 years before the engine. It has 1200 miles on it. Have good compression on all cylinders. Sometimes it blows blue smoke sometimes it doesn't. Have dual exhaust and the right side blows more than the left. There is oil in the right tailpipe. Some of the smoke I'm sure is due to the rings still being bedded. It seems to blow smoke when it gets hot. It is not running excessively hot though it does run on the upper end of the opperating temp, but this is nothing new, it has always done that. I got it hot enough to blow smoke last night and did a compression test with it still hot. The compression was signifacantly less (around 150 psi) normally 175 - 185. Started with the right side and as it move to the left side the engine had cooled some and got excellent compression. Did the right side one more time and since it had cooled it returned to normal. All cylinders are 175-185 psi within 6 cranks of the engine. I suspect that it is due to the difference in heat expansion between the cast iron block and the forged pistons. My question Is this caused by bad machining. It was done by a reputable shop, they had the whole kit including pistons and rings, and the pistons fit like a glove when I got it back. It seemed like pretty solid work with good machining. I am working on making the car run cooler, but I was wondering if anyone has experience with this type of problem and what can be done about it.
 

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If oil is going by the rings after 1200 miles then you have serious problems. Do the plugs show oil? Do you have a lot of blow by present at valve cover openings? Are you using a PCV?
 

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I hate an oil burner.
First check the valve guides for the proper clearance.
Make sure you got regular tension rings & not low tension rings.
If they are plasma moly hone the cylinders to at least a 500 grit & have the bores honed with a plateau brush.
If you do this that will stop most of the oil consumption.
The forged pistons do not help the situation, but they are bullit proof unless you fry a piston with too lean a WOT throttle mixture.
Good luck. Bill
 

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Discussion Starter · #4 ·
Don't think they are low tension rings. It has been almost 2 years since I assembled it. I got the kit from flatlander racing. I meant to call them today but they closed before I got to it. The thing is it doesn't do it all the time. Just when it is getting on the edge of the operating temp. Has crappy compression when it's hot and it gets better as it cools. I'm installing an aluminum radiator with electric fans soon. My concern with the forged pistons it that I think their thermal expansion is different from the rest of my engine and when it heats up it doesn't seal as well. Guides should be good. They were done a couple years before I got the stroker kit. They worked fine when I took them off and I had just had them redone so it almost has to be in the rings. If I can get it to run cooler with this radiator it will stop burning oil. Just worried about the block work. How tight should the pistons fit. If the cylinders were much smaller the pistons probably would bind a bit.
 

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Could be something as simple as a weeping intake manifold gasket. Do you know what gasket was used?
 

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Oil ring lands go through the wrist pin hole and on mine they had pieces that go behind the ring to minimize oil getting by but they don't work all that good......

Mine doesn't smoke any and the plugs look good but it consumes about a quart in 1200 miles....near as I can figger!!
 

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Discussion Starter · #8 ·
Not sure on the ring gap. Didn't know about gapping the rings until recently. I read the instructions that came with the rings top to bottom at least 4 times before installing them and no mention of what to set gap to or to gap them at all. Most of the mechanics I've talked to here think I just need to give it more time to seat the rings. It is showing improvement. Tonight I installed the aluminum radiator and cooling fans and it ran cooler. When I rev it up it gets hot but its the first time its ever recovered from being overheated. I think the upper end of my gauge is about 180 because the thermostat for the fan to kick on is set at 180 and it didn't come on until it was at the edge of operating range. Either way it is getting much better and I think the rings are just not quite seated yet. More when I drive it around some
 

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right side oil burner .. 1200 miles rings should not be the problem if installed correct . none are upside-down , correct gap and hone finish

valve seals , . What type ? ones that stay on the guide or stay on the stem ?

Clevelands are know to fill the right valve cover w/oil at high rpm .

oil return to pan is the first/most important oil mod. .

oil wt. in the pan ?
 

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If the rings are installed correctly, they've seated already.

Answer Dan's questions and I think you'll get it figured out.
 

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Discussion Starter · #11 ·
right side oil burner .. 1200 miles rings should not be the problem if installed correct . none are upside-down , correct gap and hone finish

valve seals , . What type ? ones that stay on the guide or stay on the stem ?

Clevelands are know to fill the right valve cover w/oil at high rpm .

oil return to pan is the first/most important oil mod. .

oil wt. in the pan ?
Followed all instructions when assembling pistons. Cylinder hone belongs to machine shop but they had the whole kit when they did it. Valve seals stay on stem. Just replaced them with viton seals all the guides look good. Curious about oil mod. Every time I shut off engine I hear oil dripping back to the pan and I know the cylinder heads are filling up to some degree. Ran it for about 2 hours last night with minimal smoke. Getting better while it idled. I just switched from 10-30 to 10-40. I changed the oil at about 500 miles because it was really black. Started up engine and within 5 minutes of running it was just as black. Suspected the oil wasn't getting filtered but checked it and oil was coming out filter hole. Changed oil last night, ran car for 2 hours and oil is looks good this time. Mabye I just didn't break it in right. When I ran it last night I would let it idle, rev it to 2500 for a few minutes and repeated that a few times and that seemed to help tremendously. I think it will be alright but it's hard to say this soon.
 

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Oil going into pan from heads is a lot quieter than oil going into pan from the Valley's various drain places.

Valley drain back is ploppy like a not quite off kitchen sink.
FE , tell me about the Cleveland block(s)
 

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If the rings are installed correctly, they've seated already.
That's a 100% certainty?

How did he gap them? Said there were no instructions.

If these are stroker pistons with the ring lands @ the wrist pin, they just certainly may leak (oil ring) on a street engine. Anyone one have a blow-by meter?
 

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Followed all instructions when assembling pistons. Cylinder hone belongs to machine shop but they had the whole kit when they did it. Valve seals stay on stem. Just replaced them with viton seals all the guides look good. Curious about oil mod. Every time I shut off engine I hear oil dripping back to the pan and I know the cylinder heads are filling up to some degree. Ran it for about 2 hours last night with minimal smoke. Getting better while it idled. I just switched from 10-30 to 10-40. I changed the oil at about 500 miles because it was really black. Started up engine and within 5 minutes of running it was just as black. Suspected the oil wasn't getting filtered but checked it and oil was coming out filter hole. Changed oil last night, ran car for 2 hours and oil is looks good this time. Mabye I just didn't break it in right. When I ran it last night I would let it idle, rev it to 2500 for a few minutes and repeated that a few times and that seemed to help tremendously. I think it will be alright but it's hard to say this soon.
return mods...
chamfer returns in head
place head gasket on head , grind return holes front and rear to gasket
gasket on block , do the same as heads
front valley , grind that opening to valley floor level .. bloocks with J suffix , chamfer rear returns
some I open the return holes .040"
 

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Oh absolutely. I'm a wizard and I don't need to see or tear down any engine to know exactly what's wrong with it.

I seem to lose sight that not everyone's a wizard.
Well, that explains the pointy hat...


It would take someone with a direct tie to PSYCHOTIC HOTLINE to make the generalized statement you did.
 

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That's a 100% certainty?

How did he gap them? Said there were no instructions.

If these are stroker pistons with the ring lands @ the wrist pin, they just certainly may leak (oil ring) on a street engine. Anyone one have a blow-by meter?
KLUTZ , why would pistons leak oil past the ring , when part of the wrist pin is in the oil groove ?

you know what correct hone and ring install is/means ?
 
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