krusty

the reason behind my thread on port matching led me to find something real bad , ok today i noticed some white smoke comming from the left bank of the engine , it went away after i adjusted the mixture , but not long after blue smoke started comming from the left bank , i had someone comming around to tune it and he said that the inlet gasket was shot and that oil was comming into the inlet ports , he pulled out number 7 plug and it was fouled with oil , no drama`s i thought , i will just change the gasket ,

while changing the gasket i noticed alot of oil in the inlet port , i pulled out the plugs and decided to blow some out by cranking the engine , upon doing this i noticed there was almost no compression , the rest of the cylenders had plenty but number 7 has none ,
when i put my finger over the plug hole i can hardly feel any thing ,

any suggestions on what the problem is , maybe a broken ring , cracked piston , cracked block , im up for any suggestions

Xtreme F6

Surely if its that bad the engine would have been missing its head off with a dropped cylinder..........

davis

It could also be a "top end" problem. A worn valve guide, bad valve seal, stuck valve, etc. Oil may have gotten under a valve at the seat and formed a deposit that has crysalized due to the heat of combustion and is keeping the valve from properly sealing. Too much valve lash can also cause a valve to not seat properly.

Turn the engine over by hand with the rocker cover off on 5-8 bank. Wait until the valves are both seated on the bottom of the compression stroke and spray some WD40 into the cylinder through the sparkplug hole. You don't need a lot, perhaps 2-3 tablespoons at most. Bring the piston up to the top (using the starter) and see if the compression increases and if you blow WD40 past the guides/seals with a compression tester on the sparkplug hole. Your finger isn't a very good measuring tool, but if you don't feel hardly any compression, you can be sure that there is some kind of problem. Use a compression tester to measure it and, particularly, the effect of testing compression with a light oil in the cylinder while cranking.

If, during testing, your compression does not raise with the oil in the cylinder, try backing off on the rocker arm fasteners on that cylinder. Give them a couple of turns and try again. If you get an improvement, lash might be the culprit. If you can't see or feel any oil coming past the guides, then you may have a more serious problem.

You can drain your oil pan into a coffee filter or cheese cloth and cut open your oil filter to look for fragments of metal. If found in any reasonably large size, you will probably need to rebuild the engine.


:davis:

soverign

Did this just happen out of the blue,or did you change something recently,like say,the cam and lifters?

krusty

thanks fellas , i will give your trick a go DAVIS ,
SOVERIGN the engine was a second hand engine i bought from someone on this site , the engine seemed fine , the bore looked good , it is 30 thou over , hypertec pistons, ect ,i just had to put my own cam and top end on it ,

i first ran the engine last weekend and there seemed to be no problems , only yesterday the problem started .

soverign

I'd be having a quick look at the cam lobe and lifter on that pot,just to make sure it's okay..

davis

Regardless of what anyone says, my opinion is that hypereutectic pistons are JUNK. If you want to put them into a stone-stock "cast piston replacement" role, fine, but that is all they are worth IMO.

It is my very strong opinion that any engine builder, whether professional or hobbyist, that uses hypereutectic pistons in a "performance application," should be shot on sight. And, certainly, any Cleveland engine qualifies as a "performance application" by the very nature of the engine design. However, I am perfectly happy to accept the role of "mule engine" in a domesticated ute or other, absolutely pure-street, application. This would be one where its builder focused solely on producing maximum torque in an off-idle to ~4000 maybe even 4500 RPM role. ...the kind of application where .460" lift is considered "big."

I don't mean to be rude to those who swear by them. I don't mean to be insulting to anyone who believes that they are a fantastic product. I'm happy that people have the choice to choose their own paths. I personally wouldn't choose that path if I was falling down a very tall flight of stairs and that was the only way to save my arse. I'd rather end up at the bottom and start the job over doing it the "right way."



:davis:

krusty

ahh ive found the problem ,
just make sure your sitting down for this one fella`s,

well after plenty of head scratching (and ball scratching) i decided to remove the left head ,
the piston looked fine , no holes or visable cracks ,
the heads looked ok too , the heads were off another engine and were reco`ed ,

i used a plastic lid from a paint mixing cup and placed it over the cylender, cranked the engine while holding the lid down ,
number 7 cylender did nothing while the others sucked the lid in and blew it out , so i knew that there was something wrong with that number 7 piston ,

i removed the engine from the car then removed the sump ,
i went to undo number 7 rod cap and noticed the bolts were only finger tight ,
mmmm i started to worry a little ,
after removing the cap and having a quick look at the bearing it was time to pull the piston out to see what the drama was ,

i nearly shIt myself when i looked at the piston , it was`nt a craked piston , no holes in the piston , no broken rings , IT SIMPLY HAD NO RINGS AT ALL , NO COMPRESSION OR OIL SCRAPER RINGS , NOTHING .

after i picked my jaw up off the ground i started laughing , it was either laugh or cry

i had a bad feeling from the start of the instalation , and that gut feeling was correct , and to think yesterday my mates were calling me parenoid

xdclevo

No rings hey
Did it have much blowby, or didn't it get a chance to get any cly pressure?

krusty

i did notice some exesive blow by and i asked the mechanic if that was ok and he said it was ok,
there was only one piston with no rings number 7 ,
i would say that the previous owner has removed that piston for some reason and just put it back and then sold it ,
let that be a warning to people buying parts off people internet site`s ,