GAAAAHHH...any input on confirming possible leaking head to cylinder, cruises nice but sounds like leak under load/rough idle Options

[orange914]

heres the skinny, we just got the new 2056 installed at a local shop. it fired right up, good fuel & oil pressure, real responsive. it idles abit rough with an occasional pop thru throttle body at idle. shop owner took it for a ride and said it felt like it was a head gasket leaking. cruised good but under a load it pop,pop,popped. when we built it we checked the registers...flat. we lapped cylinders to head... check. we torqued heads... click. can possible overtorqueing create leak?

it's d-jet with a modified mps to match the engine. i'm abit frustated as it was kinda the red headed step child sitting in the corner. (IMG:style_emoticons/default/dry.gif) i know there will need to have further work to clean up hose routing. i also know the aux. valve is NOT plumbed in yet (only issue i KNOW of). could that cause the above "possible head gasket leak sound/feel" i think everything else is plumbed good. it almost acts like a vacuum leak, or crossed plug wires, they swear there are no intake vacuum ports open and they re-checked the firing order. any thoughts on a stuck injector or maybe an intake valve may be too tight. the occasional pop thru the intake at idle makes me think it could be one of those (IMG:style_emoticons/default/sad.gif) . maybe an intake is too tight (chromoly set at 0 backlash as jake says). the valves were re-set after 20 min. break in running 30 wht. brad penn break in oil then changed to b.p. 20x50

i guess the next step is confirm wire order, get aux. valve hooked in, run a compression test. then take to a shop with a sniffer.

after a year build and many challenges my poor son kenny is burnt out. i keep telling him he's almost there. oh yeah it does have a few minor push rod tube leaks, are there different size tubes (at the o-ring?) i know from many post the o-rings getting cut seems very common.

mike

[Rand]

fired right up...real responsive

That rules out the question of crossed plug wiring.

checked the registers...flat. we lapped cylinders to head... check. we torqued heads... click.

Did they use head gaskets???? Hoping not. And if not, problem shouldn't be here.

cruised good but under a load it pop,pop,popped

Exhaust leak? Running to rich? Timing off? (Or some combination thereof?)

i also know the aux. valve is NOT plumbed in yet

Not an issue here. I don't even run one. (Well, unless you allow a vacuum leak here.)

occasional pop thru the intake at idle

Lean idle mixture? Timing? [Hmm... How's the idle RPM?]


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Ok, was just thinking out loud with you. Good luck. (IMG:style_emoticons/default/beerchug.gif)

[orange914]

fired right up...real responsive

That rules out the question of crossed plug wiring.
always alittle rough idle. that response i think they must have been from the lighter flywheel.

checked the registers...flat. we lapped cylinders to head... check. we torqued heads... click.

Did they use head gaskets???? Hoping not. And if not, problem shouldn't be here.
i didn't us head gaskets and cant imagine a leak after the detail we went thru

cruised good but under a load it pop,pop,popped

Exhaust leak? Running to rich? Timing off? (Or some combination thereof?)
no leak, timing set

i also know the aux. valve is NOT plumbed in yet

Not an issue here. I don't even run one. (Well, unless you allow a vacuum leak here.)
is aux air only for idle improvements?
i still suspect a leak somewhere.

occasional pop thru the intake at idle

Lean idle mixture? Timing? [Hmm... How's the idle RPM?]
if anything idle may be rich, thats what makes me suspect a stuck/sticking injector(s), the pop at load could be a lean miss fire (IMG:style_emoticons/default/confused24.gif) i need to have it check on a co/hc anylyzer ----------
Ok, was just thinking out loud with you. Good luck. (IMG:style_emoticons/default/beerchug.gif)