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JohnZ or anyone else welcome - head question

Kid_Again

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JohnZ;worship


...thanks to anyone else who can help

...i have the small block back on the road and the essential modifications are new JEGS aluminum heads (small intake runners, 2.08" intake valves and 72cc chambers to keep the compression reasonable) plus the vortech blow-through carb kit..i also note that I installed a boost timing master and have yet to have the need to use it, but it's there if i need to back off on the timing

...i have lots of little tunig stuff to do but here's the major problem...it goes back to one reason why i changed out the old iron eagle heads (in addition to allowing a higher CR with aluminum heads)....the intake manifold did not sit low enough in the valley which allowed oil infiltration into each cylinder and i had two possibilities, either the heads or the block deck was not milled flat and i decided to keep the block and give the new heads a try.....

..the problem is that i have a slight coolant leak on the rear of the driver's side, where the head meets the block..i used new head gaskets, of course, but i wonder whether the heads are tight enough because i sent an email to ARP, asking them for the head bolt torque specs....i'll have to dig up their email but they gave two specs, stock and a lower torque spec if the ARP bolt lube was used and since i had the lube, i followed the latter route...

..so, do you think i haven't torqued them tight enough or are there other things to consider?

...since i was off a few extra days over the holiday, I decided to play around with some ideas....one, which was volunteered by VNV, was for me to torque down the bolts to stock specs since i am so ****ed that it looks like i'm going to order a zz383 short block and start over again - so there's no big deal if i pull the threads....

...i did something in between, i added another 5 ft/lbs of torque to each bolt in the correct pattern (it appears the original torque setting was about 45 ft/lbs if my clicker is correct) AND i added some gack which is advertised to seal head gasket coolant leaks...i know, i know, that's a bubba fix but both fixes together have really cut down on the leakage.....any thoughts, besides going with a new short block????


..as an aside, i have LOTS of little things to dial in, for example, the oil supply to the compressor..in short, i had an oil leak at the compressor and it was clear that the problem was NOT the high pressure inlet line - the return line kinked on me and i was having blow-by at the hose fitting on the compressor:eyerole...so, i did a "VNV", made sure i had a large loop at the compressor and nylon tied the return line securely to the compressor bracket to keep the correct orientation and move it away from the headers......i immediately noted a 5psi drop in oil pressure at the gauge and now i have no leaks...it appears my beloved engine rebuilder put in a high pressure, high output oil pump during the rebuild and perhaps that ultimately made sense, given how i modified the oiling system...yeah, they all came from the factory that way:D

...any thoughts are welcome!
 
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..the problem is that i have a slight coolant leak on the rear of the driver's side, where the head meets the block..i used new head gaskets, of course, but i wonder whether the heads are tight enough because i sent an email to ARP, asking them for the head bolt torque specs....i'll have to dig up their email but they gave two specs, stock and a lower torque spec if the ARP bolt lube was used and since i had the lube, i followed the latter route...

...i did something in between, i added another 5 ft/lbs of torque to each bolt in the correct pattern (it appears the original torque setting was about 45 ft/lbs if my clicker is correct) AND i added some gack which is advertised to seal head gasket coolant leaks...i know, i know, that's a bubba fix but both fixes together have really cut down on the leakage.....any thoughts, besides going with a new short block????

Gotta ask - did you clean the threads in the block and use non-hardening thread sealer on every bolt, and what kind did you use?

:beer
 

IH2LOSE

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My questions

With the original heads ,Did you have coolant leaks?


are both heads leaking or just one.

Have the heads been on and off the car after torquing ?


What type of gaskets did you use.

Soory your having troubles with this
 

Kid_Again

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Gotta ask - did you clean the threads in the block and use non-hardening thread sealer on every bolt, and what kind did you use?

:beer


chased the threads with a thread chaser but only used the ARP lubricant on the threads
 

Kid_Again

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My questions

With the original heads ,Did you have coolant leaks?


are both heads leaking or just one.

Have the heads been on and off the car after torquing ?


What type of gaskets did you use.

Soory your having troubles with this

OK, Larry here are my responses...

I did not have coolant leaks with the old iron heads, i only had the oil leak previously mentioned

Only one head is leaking and only in the one place noted

Neither head has been off after torquing

I used solid copper head gaskets and i will dig up the receipt and post the brand


Parenthetically, I've only run the engine for maybe an hour or so, some of that time being spent idling while i've futzed with the various little things that need to be done...another example being that i had to construct a new throttle linkage since the leverage point for actuating the carb is substantially higher than the factory setting...once i got the geometry set correctly, i still had major league problems with a consistent idle.....

...i noticed, once i removed the blower cover, that the primary throttle plates were not consistently seating at idle because it appeared that the Vortech in-the-blower-box linkage was binding...the most efficient (as opposed to the best) solution was to add a light throttle return spring inside the carb box and that fixed that problem without adding a heavy pedal pressure....BUT, I still had an unstable idle

...the only possible solution was a vacuum leak and darned if the PCV hose wasn't loose....substitued new hose clamps and now she will idle all the way down to 600rpm and hold that idle....Mark was concerned that my previously high idle was kicking in the vacuum can and that was good advice, although the car runs stone cold at idle...

....i guess the final tidbit (all of this will going into the novel that I'm writing and will post here) was the problem that i had adjusting the valves once i put on the new heads...the same old story, if you add new pieces not necessarily meant to go together, you have to work at making it all come together......after four tries, i now have the valves adjusted to the point where they sound like a sewing machine (solid lifter cam), nice and tight...i had to take them down an additional .002", versus what i had with the iron heads.......i finally made it easier for myself, i used the solid lifter valve adjustment instructions provide me by 4WDVETTE, cut the top off an old distributor cap, marked the #1, 4, 6 and 7 spots in the cap and just went methodically over each valve - got the time down to 15 minutes...one note of caution, i use an MSD distributor and they key the cap differently than standard so you have to have to re-orient yourself to the location of #1 on the newly clocked cap...


....of course, i left out the part about the roller rockers not clearing the base of the rocker studs and the "engineering" needed to overcome that...but i digress:eyerole
 

Tom Bryant

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...i have lots of little tuning stuff to do but here's the major problem...it goes back to one reason why i changed out the old iron eagle heads (in addition to allowing a higher CR with aluminum heads)....the intake manifold did not sit low enough in the valley which allowed oil infiltration into each cylinder and i had two possibilities, either the heads or the block deck was not milled flat and i decided to keep the block and give the new heads a try.....

...any thoughts are welcome!


I picked up two things from this paragraph. One is that you state the intake does not sit low enough in the valley and 2 you suspect that the block and/or heads were not milled correctly. Since you have new heads I'd think that you did not cut them but how about the block? How much has it been decked from stock? When you remove material from the block deck or the head surface the intake surfaces get closer together. The intake manifold also has to be milled to allow it to set in the valley properly. The machine shops have a formula that tell them how much to cut an intake based on the block and head cuts.

On my 355 I didn't deck the block but I took .020 off of the heads to set my cr at 9.3:1. I had 3 intake manifolds that would still fit and tighten down but the Offy I wanted to use was too wide and would not sit down in the valley. There was plenty of room on the front and rear to block surface but the intake port surfaces were too fat. I blame this on manufacturer error. I had some material taken off of the intake and it bolted right on.

Your new heads are probably cut a little fatter than the Iron Eagles. Have your machine shop mill a little off of the intake to allow it to sit down lower. Since you need such a small amount cut it may be trial and error. Also did you check the cut angles of the intake and the heads to see if there is a gap at the top or bottom of the port? With the intake setting in the valley with no gasket the angle of the head cut and the block cut should be exactly parallel. An incorrectly cut angle here will cause a sealing problem too.

Tom
 

Kid_Again

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I picked up two things from this paragraph One is that you state the intake does not sit low enough in the valley and 2 you suspect that the block and/or heads were not milled correctly. Since you have new heads I'd think that you did not cut them but how about the block? How much has it been decked from stock? When you remove material from the block deck or the head surface the intake surfaces get closer together. The intake manifold also has to be milled to allow it to set in the valley properly. The machine shops have a formula that tell them how much to cut an intake based on the block and head cuts.

On my 355 I didn't deck the block but I took .020 off of the heads to set my cr at 9.3:1. I had 3 intake manifolds that would still fit and tighten down but the Offy I wanted to use was too wide and would not sit down in the valley. There was plenty of room on the front and rear to block surface but the intake port surfaces were too fat. I blame this on manufacturer error. I had some material taken off of the intake and it bolted right on.

Your new heads are probably cut a little fatter than the Iron Eagles. Have your machine shop mill a little off of the intake to allow it to sit down lower. Since you need such a small amount cut it may be trial and error. Also did you check the cut angles of the intake and the heads to see if there is a gap at the top or bottom of the port? With the intake setting in the valley with no gasket the angle of the head cut and the block cut should be exactly parallel. An incorrectly cut angle here will cause a sealing problem too.

Tom


Very good thoughts, Tom, appreciated.

I don't have many answers. While I have the receipts from the engine rebuild, there is no notice, one way or the other, about the block being off (nor any mention (or cost) about the need to mill the deck. The engine rebuilder is now out of business. Gee, I wonder why.

I did not measure the heads before I put them on. I did, however, do as you suggested and put the intake flat on the heads before assembling the intake manifold and i DID notice one difference. With the Iron Eagle's I came to realize that the intake just didn't SOUND like it was sitting flat on the heads - it had a BIT of ring to it. The new intake (low rise Torker II) hits the new heads (not dropping it, just being graphic) with a thud. Visual inspection fore and aft, along the sides and to some extent from the lifter valley using a mirror and flexible light demonstrated a tight, consistent fit.

Since I had to use gasket maker to seal the previous runners, I added a thin seal of gasket maker to the flats of the new intake and placed that on the new heads with no fastening. When I pulled the intake back off, the glue pattern was consistent all around the runners, whereas it was DEFINITELY thicker at the bottom using the old heads and old manifold.

Not proof positive but these are the data that I used to convince myself that the problem was with the heads.

I WILL say that I did have a problem with a pulled thread on THE OTHER side but there are no leaks there once I tapped in the insert.

All the plugs appear fine...a little rich but nothing like the old days with the oil infiltration. Besides, it needs to be driven, not just ilded for me to be convinced the plugs are a reflection of reality.

Fires up and smoothes down to an idle in a way it NEVER did before. At least I don't have to worry about Bubba working on the engine and charging me top dollar for crappy work.
 

Tom Bryant

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Re-reading I see that you said the leak was between the head and block and that you said the intake problem was with the old heads. I think you are going to have to remove the head bolts and reinstall them using the non-hardening sealer as John said. I don't think that the ARP thread lube will stop the coolant from seeping past the threads once the system is under preasure.

Tom
 

Kid_Again

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Re-reading I see that you said the leak was between the head and block and that you said the intake problem was with the old heads. I think you are going to have to remove the head bolts and reinstall them using the non-hardening sealer as John said. I don't think that the ARP thread lube will stop the coolant from seeping past the threads once the system is under preasure.

Tom


Yup, I think you're right. I'll wait for brand recommendations it there are any.
 
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I've used Permatex #2, Permatex Thread Sealer, and ARP Thread Sealer on the head bolts on many engines over the years; I clean the block threads with a stiff-bristle bore brush and lacquer thinner first to make sure they're clean. Thread sealer (absolutely essential with wet-deck engines like Chevys to avoid the problem you're seeing) requires clean, dry threads in order to work.

:beer
 

Viet Nam Vett

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Got it Kid..... Get the Cigars and Mar-Tunies ready...It's tare down time...:D....Ahhh..lets see..that should be #5 on the Valve Adjustment..
 

Kid_Again

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yup...the experts have spoken


;worship

permatex #2 it is...amazing that i had so little problems, given the reality of the situation

.......and Mark is correct, this will be the fifth time since i started the rebuild that i will have adjusted the solid lifters....i've got it down to a science....


....funny how i used to dread doing tasks like valve adjustments or finding #1TDC, or i would take them to my buddy who's been working on these cars for years.... a few less things to be dependent on someone else......



STILL thinking about getting that 383 short block...but THAT will be NEXT year's project....I need to swap the other car's 4bbl big block intake manifold for my newly refinished tripower setup....now that should result in a few posts for help:W


..thanks again, guys
 

Kid_Again

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three freakin' auto supply places before i found one that had permatex #2:eyerole



....hmmm, never thought about the phrase "wet deck" before...might be an interesting handle for the CAC...."I got 'ya wet deck - RIGHT HEAH!!!"
 

Tom Bryant

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three freakin' auto supply places before i found one that had permatex #2:eyerole



....hmmm, never thought about the phrase "wet deck" before...might be an interesting handle for the CAC...."I got 'ya wet deck - RIGHT HEAH!!!"

Ok...Put the cap back on the Permatex. :L
 

Kid_Again

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bossvette

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I know those frustrations, I'm leaning towards a misfitting intake due to possibly cut heads on my 52 F1 as the leading culprit in its woes. Tear the whole thing apart again.:eek:hnoes:eek:hnoes
 

Kid_Again

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....well, i had to tear the head off and start over again....


...i was at VNV's yesterday and helped him with his AC project, i gave him a few helpful hints and he repaid the favor...i had an oil leak on the blower that was driving me nuts and i kept thinking it was the oil exit line so he suggested that i remove the blower....which i had to do to pull the head....

.....after much inspection, i finally found the problem - the factory has three plugged holes on the bottom of the blower and every friggin' one was loose...i know, i know, i should have gone over it before :eyerole...all i need is a new intake gasket and i'm ready to get it back on the road
 

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