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

[SirAndy]

exhaust leak, valves, timing, all the above ...


i thought head gaskets on a T4 were a thing of the past!?!?
(IMG:style_emoticons/default/confused24.gif) Andy

[euro911]

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.

Check all the ELECTRICAL CONNECTIONS, esp. at the INJECTORS
Verify there are NO VACUUM LEAKS, anywhere ... including hoses
Perform both, COMPRESSION and LEAK-DOWN tests ... that will tell if you have leaks in the combustion chamber


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?)

YES -
INNER (at case) 21.3mm ID
OUTER (at head) 25.5mm ID


i know from many post the o-rings getting cut seems very common.

Its a possibility

[orange914]

exhaust leak, valves, timing, all the above ...


i thought head gaskets on a T4 were a thing of the past!?!?
(IMG:style_emoticons/default/confused24.gif) Andy

no head gaskets here... his words, i should have been more clear. but thats also what makes me think he's wrong. i guess a compression check is next. after a weekend of thess (IMG:style_emoticons/default/beer3.gif) (IMG:style_emoticons/default/beer3.gif) (IMG:style_emoticons/default/beer3.gif) (IMG:style_emoticons/default/beer3.gif) (IMG:style_emoticons/default/beer3.gif) (IMG:style_emoticons/default/beer3.gif)

i dont think exaust leak because of acompaning engine cut out. it has the oversized new studs from jack, besides i even annuled the copper seals...

i really hope it's an injector or maybe aux air not being hooked up yet. (IMG:style_emoticons/default/headbang.gif)

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?]


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

[orange914]

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.

Check all the ELECTRICAL CONNECTIONS, esp. at the INJECTORS
Verify there are NO VACUUM LEAKS, anywhere ... including hoses
Perform both, COMPRESSION and LEAK-DOWN tests ... that will tell if you have leaks in the combustion chamber

looked over "new harness" seems good, seems only possible hose routing is needed is to hook in aux valve. the shop says there are no open ports but i really need that re-checked, even so i'd think an open aux valve port at intake would really show up more at idle?? what do you think about the aux. valve being a possible cause

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?)

YES -
INNER (at case) 21.3mm ID
OUTER (at head) 25.5mm ID

we had a set of narrow and a set of "chubby" tubes i believe we used the narrow ones, the case is a 74 2.0 and the heads i believe are 74's also. do you know which are compatable?

[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)

[toon1]

MIke is the AAR plumbed in?

I thought we did that.

If so, it might NOT be working. That will cause a lean miss issue( BTDT).

If it where a head to cyl. leak you would hear it hissing( I thought the same thing about my motor , it's fine).

If the engine fired right up, the plug wires are fine.

Timing may be off but would have to be way off.

The possibility that the engine needs MORE fuel right now because it's new is there( less likely, but I've seen it happen).

BTW- congrats. on FINNALLY getting it running.

[Cap'n Krusty]

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.

Check all the ELECTRICAL CONNECTIONS, esp. at the INJECTORS
Verify there are NO VACUUM LEAKS, anywhere ... including hoses
Perform both, COMPRESSION and LEAK-DOWN tests ... that will tell if you have leaks in the combustion chamber


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?)

YES -
INNER (at case) 21.3mm ID
OUTER (at head) 25.5mm ID


i know from many post the o-rings getting cut seems very common.

[color=#3333FF]Its a possibility

Just so you know, there are TWO DIFFERENT outer pushrod tube seal o-rings, very early and everything else. The Cap'n

[euro911]

Just so you know, there are TWO DIFFERENT outer pushrod tube seal o-rings, very early and everything else. The Cap'n

That, I didn't know (IMG:style_emoticons/default/confused24.gif)

Thanks for the extra tidbit of knowledge, Cap'n (IMG:style_emoticons/default/shades.gif)

[orange914]

MIke is the AAR plumbed in?

I thought we did that.

If so, it might NOT be working. That will cause a lean miss issue( BTDT).

If it where a head to cyl. leak you would hear it hissing( I thought the same thing about my motor , it's fine).

If the engine fired right up, the plug wires are fine.

Timing may be off but would have to be way off.

The possibility that the engine needs MORE fuel right now because it's new is there( less likely, but I've seen it happen).

BTW- congrats. on FINNALLY getting it running.

keith
it's real close... i think...
no we were short the hoses to hook it up, so i wanted the shop to go ahead and finish a few things which they didn't. (IMG:style_emoticons/default/dry.gif) we drove it home for a break then sort it out for the next step. i figured we'd look over a few things after a weekend break from it.

i'll keep you up on it

[orange914]

even though i promised to let it sit this w.e. i couldnt help but look at the firing order on the 914 as it sits. off the top, i think it should be clockwise 1432... it's set on clockwise 1243... (IMG:style_emoticons/default/idea.gif)

i've promised myself i wouldn't mess with it now but i'm a junky for this crap and may just have to break my word... at least to confirm the order

hi, my name is mike and i'm an adict (IMG:style_emoticons/default/wacko.gif)

[kconway]

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.

Check all the ELECTRICAL CONNECTIONS, esp. at the INJECTORS
Verify there are NO VACUUM LEAKS, anywhere ... including hoses
Perform both, COMPRESSION and LEAK-DOWN tests ... that will tell if you have leaks in the combustion chamber


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?)

YES -
INNER (at case) 21.3mm ID
OUTER (at head) 25.5mm ID


i know from many post the o-rings getting cut seems very common.

[color=#3333FF]Its a possibility

Just so you know, there are TWO DIFFERENT outer pushrod tube seal o-rings, very early and everything else. The Cap'n

I noticed the pushrod tubes I got from Jake were different from what i pulled of my car. The "groove" where the seals sit were narrower then what came off my car. Seals seem to fit better.

[r_towle]

1432 is the holy aircooled firing order.
It will run and sound decent the wrong way.

1432 1432 1432

Rich

[orange914]

1432 is the holy aircooled firing order.
It will run and sound decent the wrong way.

1432 1432 1432

Rich

thanks... (IMG:style_emoticons/default/beerchug.gif)
i'll sleep better tonight and keep my hands off promise

p.s. i couldn't help but wonder if the 9550 cam had a different f.o.. just like small block ford. the 351w is different than 289/302