Guys I wrote about this before but I thought the issue had resolved itself, but it hasnít.
The new motor is now 2000kís old and sounding/feeling great. But driving along at a steady 3500rpm upwards Iím puffing out quite a bit of blue smoke, but only after maintaining those revs for a few kís.
Accelerating under full load 1000-6500 rpm there is no smoke coming from tailpipe, and not a whiff of blow-by coming out of the rocker covers thru the pvc at idle or when holding throttle open at 3000rpm free revving.
Also there is no smoke at start up and the only time it does it is at a steady cruise under load at 3500rpm up.
So doesnít seem like ring issues or valve stem seals. Any suggestions? What are the symptoms of too much oil in the top of the motor? Iím not running an oil restrictor kit on recommendation of engine builder.
Iíll pull the plugs when it cools down to see if it is to do with one cylinder or not, but expecting all the plugs will be equal.
I reckon it's possibly trans fluid. It could be either the trans is over full or the modulator on the back of the auto is stuffed.
Check for trans fluid @ the vac kickdown line. The check the box's fluid isn't blowing out of the breather onto the exhaust. Before I got a decent C4 built mine used to always blow it's contents out of the breather onto the exhaust. I believe it was over pressurising but no-one would believe me. Hey I only had to drive the car almost every day So what would I know? lol
Could also be the trans oil boiling? Hence coming out the breather.
I was about to launch into one about the motor not being run in properly yet, rings not seated etc.
Or the motor being so efficient, you had not put sufficient load on the rings and may have glazed the bores.
But brenx is on to something I think, and you obviously know what to look for ring wise.
My new motor, much milder than yours, has produce some huge plums of smoke at the end of the quater.So much so, staff at the strip have said, you had better check that out mate.
It still runs fine and the only thing I can put the smoke down to is may be trans oil blowing back through the filler on to the extractors.
When my C4 let go in my old XY, the smoke coming out of the trans breather was distinctly white (due boiling trans fluid - the pipe to the cooler was blocked). It resembled a James Bond smoke screen - literally!
Isn't blue smoke related to burning engine oil?
Could be that special moonshine rocket fuel you're using!!
Yep trans fluid is grey or white..
Seeing its at part throttle I'd suspect PCV , check baffles in rocker covers, valve stem seals.I take it that rocker geometry is correct and not stuffing valve guides ???
Don't be afraid to try something new. Remember, amateurs built the Ark...Professionals built the Titanic!
Tuned & maintained by "Peppertree Perfmormance". Dart block, Scat 4340 steel crank, Custom C.P pistons.Oliver rods.. Mal Wood twin plate clutch.. Twin SC61/2's,482 rwkw/ 645 rwhp..
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Guys thanks, firstly because I wasn't excluding the trans as a possible culprit myself and 2nd that with the frickin money I spent on that motor it wouldn't want to be a bad ring sealing issue. Thirdly, try as I might today, with head cocked backwards examining the plume of smoke, I really couldn't tell exactly where it was coming from as the exhaust now exits under the diff..
Brenx the box is a top dollar rebuild by WA's best auto builder at a cost of $1900 including convertor. Can't do much more than that.
Suppose the next thing to do is try to block the C4 breather or pipe it elsewhere and see what happens.
I'll let you guys know what happens after I pull the plugs tomorrow and try the above tomorrow.
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