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Current Page: 2 of 3
Re: Checking for warped heads
Posted by: MattNall ()
Date: February 15, 2009 06:31PM

Actually you can run the straightedge on the valve cover surfaces.. top and bottom... they tell the same thing...

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: cnicol ()
Date: February 15, 2009 08:00PM

It's not "normal" to have studs unscrewing from the block, especially the lower studs which rarely pull out or unscrew. What caused the block to relax when it normally grips the studs firmly? Also, the notion of a head being "loose" and needing "retorquing" isn't one that comes to me after working on hundreds of these engines. What would cause the engine to loosen up like that - after all there are twelve studs each pulling the heads down with hundreds of pounds of force - why would that force suddenly (or not so suddenly) relax so the head gasket could start leaking and eventually burn through? Is it possible that your motor got baked some time along the way?

Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
61 Seamist Jade Rampside 140 PG
60 Monza coupe (sold, sniff sniff)
66 Sprint Corsa convt - First car! Re-purchased 43 years later
2+2 gnatsuM 5691

+17 Tons of parts

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: ScottS ()
Date: February 15, 2009 09:27PM

Maybe one cylinder is short. Not unusual I guess to mix parts when rebulding an engine, I guess you can't assume all the cylinders are the same height unless you check them , and the gaskets too.

Having the studs loosen out of the engine when loosening the rocker studs seems to be pretty common- sure would be best to hold the studs frm turning when the rocker nuts are broken loose- doesn't clarks sell a ball that is sued to install the studs so that the rocker stud/head nut doesnt bind up and take them back out again

I don't think more torque is a good idea until you check everything , all you may do is pull the studs out of the block.

Photobucket - Video and Image Hosting
1969 Monza Coupe
1966 Nader Invader !
1966 Monza Coupe
www.vaircooled.com
I love Corvairs
Ohio

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: Darrin ()
Date: February 16, 2009 02:33AM

Mark,

How many came out? When I have had one or two come out I have just left the rocker nut/stud on the long cylinder stud and just put it back as a unit, torquing it to proper spec with no problem. You have to check with the head off though to make sure that it has proper interference fit..i.e. it turns back into the block with some difficulty.

You do not want to do this routinely...much better to keep an eye on the stud as you are loosening the rocker stud/nut and hold the long stud with a vice grips next to the cylinder to keep it from turning...guess we should have mentioned that earlier.

Take care to put them back in the same place as well.

Darrin

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: Tom Z ()
Date: February 16, 2009 03:38AM

..ok,is the engine the orig turbo block with early lo-hp heads,or the EM-84hp swapped in?..I don't consider the 'different' 3/8-16 block threads ones you want to keep 'screwing' with,like 'stretch' head bolts on newer engines..hard to tell whether the stud unscrewed,or has pulled straight out,shearing the aluminum threads in which case the stud will never hold proper torque..aside from drilling/pinning the stud in the block,using Loctite stud locker on clean/dry block threads could work ( but cross your fingers on that..)..IMHO:: if this is a temporary-driver engine,being an early-84hp,do what you can short-term,and start building another 164 engine with 65-up gaskets/jugs for a turbo..btw,I wouldn't use never-seize on the threads,I've seen/heard of using it on rocker balls,valve stem-guides (not the first choice),and shroud bolts,but have had it cause things to loosen up over time,like set screws..

Tom Z,,Rochester NY

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: Mark M ()
Date: February 16, 2009 07:36AM

Let me try to clear some things up - I'm sure my descriptions added to the confusion:

1. Engine case is original turbo, heads are 80 - 84 hp with carbs. Doubt this engine was ever "baked". Previous owner is good guy and said it ran well. He pulled it when he bought car in '75 in order to restore to turbo, and ran another engine.

2. The long head (block) studs did not pull out when I pulled rockers to retorque head. The rocker arm studs (which double as head "nuts") came off when I pulled the rockers and their nuts off. Only three came off. I am pretty sure the long head studs remained in position because the rocker arm studs turned loose easily. This was all on the left side. Right side is where I have the low compression and chirp.

3. Never thought to hold the long stud with vice grips - can't see it with shroud on.

4. After Matt's post above re: straightedge and valve covers, I now understand how to check head for warpage. (Duh, check the valve cover side, not the jug side.) Same thing a club member told me 3 weeks ago - I gotta' listen better!

Questions:
1. If I pull lower shroud can I see the long head studs so I can hold them with vice grips?

2. If it were a spark plug seat, wouldn't the O ring on the compression gauge likely make up for the leak? Any other way to check for a bad seat?

3. May as well check cyl head temp switch while when I pull head. Found it in manual, but how do I check to see if it is good? Use multimeter? What reading?

4. I have exh man. gaskets and valve cover gaskets. Other than new head gaskets, do I need any others for a short-term engine fix?

I'll be calling some club members for help as well. It's just so easy to post here - then I get understanding and what club members tell me makes it more clear.

Thanks for the help, I'll keep ya' posted after I get time on the car.

Mark M
Project: 64 Spyder Vert running 80 hp heads and carbs
1st Vair: 65 Corsa 140
St. Louis, MO
Show Me Corvair Club &
CORSA member

"If it's not broken, you're not driving it hard enough"

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: MattNall ()
Date: February 16, 2009 07:56AM

1 Forget holding the studs... you are past that! AND the Rockers STUDS cannot be held.. only the top ones.. Youare fine there!

Gaskets... maybe some JB WELD to repaior the head... really! GG


Temp SNAPSWITCH and Temp gauge Thermister are TWO different things...

T-mister is difficult to check [ fine threads on Drivers head.]

Snap switch... just put in oven and start baking... 400-600f

At 400F open oven door and read with ohmmeter... then every 25F above until you see it close [ 0 ohms] This SWITCH has COARSE threads.. and a Stabon terminal

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: Mark M ()
Date: February 16, 2009 08:06AM

Got it. Would I have a thermister on these heads? Thoght that would only be for Corsa or Spyder heads?

Mark M
Project: 64 Spyder Vert running 80 hp heads and carbs
1st Vair: 65 Corsa 140
St. Louis, MO
Show Me Corvair Club &
CORSA member

"If it's not broken, you're not driving it hard enough"

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: MattNall ()
Date: February 16, 2009 08:48AM

Correct... no T-mister... for these heads...

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Re: UPDATE & photos- RAV was right, Compression, call me stupid & ?s
Posted by: Mark M ()
Date: February 18, 2009 01:55PM

Learned a lot today - some of it bad, I think. Good news is our club meeting is Saturday so I'll take my head for our local experts to eyeball. By the way, shrouds are a pain.

Backed off rocker nuts on 1 and 5 and retested compression. 5 came up to 95, but that was it. Retested all holes and 2 and 3 came up to 130, so the valve adjustment did something. Pulled the head, #5 jug pulled out about 1/2" and #3 about 1/8. I used PB Blaster and let sit and was as careful as could be, but still pulled them some. Checked all the studs with straightedge and bottoms are all ligned up, two of tops are maybe 1/16 to 1/8,at most, in the case further, but none pulled out any.

Tested head for valve leakage using gasoline drip system - nada, no leaks at all - poured just a little at first to make sure there were no air pockets. Head gaskets were intact. Ends of pushrods are in great shape, but one is nicked - see photo and three are bent -not drastically, but evident when rolled.

BAD NEWS: Checked head with a straightedge on the surface where VC gasket goes. Bottom edge is straight, but top edge has a higher point in center (or lower point on both ends). If I hold straightedge so it is flat in center and at either end, I can get a feeler gauge under the gap at the other end. Gauge is marked .012 .315 mm. Not sure which is correct measure, .012 or .315?


Questions:

1. Can I tap the jugs back in place with a rubber mallet?
2. See photo below. #1 Exhaust and #3 intake lifters have some sort of "clip" that the others don't have. Looks like something to hold the lifter together. What is it? In photo, you can see it on right hole and not left. Why only on those?
3. 3819616 is the number on the turbo engine case. Mean anything?
4. What would cause the nick on the pushrod? - see photo
5. Is this head trash?

Mark M
Project: 64 Spyder Vert running 80 hp heads and carbs
1st Vair: 65 Corsa 140
St. Louis, MO
Show Me Corvair Club &
CORSA member

"If it's not broken, you're not driving it hard enough"

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: MattNall ()
Date: February 18, 2009 02:10PM

1 YES! most likely the paper gasket on the base didn't tear..

2 ALL Lifters need the clips! [ look in oil pan...

5 Give us closeups of each head chamber.... so we can see the gasket, etc..

And ridge or score marks in the Cylinders? [ maybe just

NONE of the cylinders looks like they were firing! Exhaust valves should be dry..

PS... POUR LOTS of gasoline in the holes!!.... no valve is leakfree....all will seep ever so slightly..

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: cnicol ()
Date: February 18, 2009 02:12PM

You can just push the cylinders back into the block by hand. If they're out enough to disengage the block, just guide them back in as you push. They're not a press fit or anything.

Some lifters have clips that cross the top, some go around the top. Either type is OK.

Just the block's casting number

Pushrod ends fail (fracture) from a lack of lubrication. Use assembly grease on all the valve train components (pushrod ends, valve tips, rocker balls) to provide lubrication when the engine is restarted with a dry top end. It takes quite a while for oil to get up there and spread around.

Can't tell what's up with that head. You should have it fly cut (gasket side) and milled (valve cover side) to provide even pressure on all three cylinders. The milling isn't optional - that's what the machinist uses for a reference dept when he flycuts the gasket side.

Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
61 Seamist Jade Rampside 140 PG
60 Monza coupe (sold, sniff sniff)
66 Sprint Corsa convt - First car! Re-purchased 43 years later
2+2 gnatsuM 5691

+17 Tons of parts

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: Mark M ()
Date: February 18, 2009 02:17PM

Nothing in oil pan when I cleaned it couple months ago, so no idea where clips are. Just noticed Craig's post -maybe different types of lifters are installed.

I'll post close up pictures of head later. Didn't look inside cylinders yet for scoring. I will.

Matt, you are right, none of the cylinders were firing 'cause the carb clogged up right after I got it started first time.

I did pour lots of gas in, even filled up the intake and exhaust. Only watched for a minute. I'll try longer.

Mark M
Project: 64 Spyder Vert running 80 hp heads and carbs
1st Vair: 65 Corsa 140
St. Louis, MO
Show Me Corvair Club &
CORSA member

"If it's not broken, you're not driving it hard enough"

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: Mark M ()
Date: February 18, 2009 03:22PM

Closeups of head chambers.

# 1 is at bottom of stroke and cylinder wall looks great. Can't feel any ridges with fingernail. Can see only an inch of 3 and 2 inches or so of 5, but they also look very good.

Can I turn engine by hand with jugs hanging like this? If so,I could see more of the wall.

Wish the club meeting was tomorrow!

Mark M
Project: 64 Spyder Vert running 80 hp heads and carbs
1st Vair: 65 Corsa 140
St. Louis, MO
Show Me Corvair Club &
CORSA member

"If it's not broken, you're not driving it hard enough"

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: MattNall ()
Date: February 18, 2009 03:48PM

Let the club guys look at it... but to me Clean it up and re-assemble!

Valves are fine if no leakage

Warpage can be fixed easily....just need a "reasonable machinist"!! A Person who does it at home?

Also.. after setting barrels back in place... scrap tops of pistons clean

Get a machinist's straightedge... lay across all 3 barrels... any gaps at the top of each cylinder?

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: cnicol ()
Date: February 18, 2009 05:44PM

Yes, you can turn the engine with the head off. You will either have to monitor the cylinders and push them back in as needed or you can put a short piece of 1/2" pipe on one stud per cylinder and use a cylinder head nut to hold the cylinder in place.

The lower gasket is a this steel ring that doesn't get any sealant or anything. It won't be affected by the cylinder moving away from the block.

Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
61 Seamist Jade Rampside 140 PG
60 Monza coupe (sold, sniff sniff)
66 Sprint Corsa convt - First car! Re-purchased 43 years later
2+2 gnatsuM 5691

+17 Tons of parts

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: RAV_AIR ()
Date: February 18, 2009 06:19PM

I'm just enjoying watching a thread titled about me being right about something. that NEVER happens. LOL

"So where do they put the engines in these things?"
"They put em where they belong....in the rear."
1964 500 coupe
Topeka, KS
Searching for a complete 95 to rebuild. (changed my mind)
If this is still in my sig, I'm still looking.
Moderator

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: ScottS ()
Date: February 18, 2009 11:28PM

Beer clean all the gorp off the block too- heat transfer rate is not so good.

Photobucket - Video and Image Hosting
1969 Monza Coupe
1966 Nader Invader !
1966 Monza Coupe
www.vaircooled.com
I love Corvairs
Ohio

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: Mark M ()
Date: February 21, 2009 04:38PM

Great club meeting today - we met at the National Museum of Transport here in town. Great old trains and nice small car collection, including Bobby Darrin's custom car from the 60's.

Cleaned up my head before I went. Center chamber had two gaskets, both outside chambers only one, but all were intact. Seat in center chamber is very rough and valves there are old - exhaust is pretty well pitted. Apparently some blow-by in #5 where the chirp was coming from. Valves in 1 and 3 are very good and obviously have been replaced. Tried the gasoline leak test and got only very slight leak from both valves in #3. Let is sit for at least 5 minutes.

Members opinion was that the head is not warped. One member will loan me his honing device to repair the gasket surfaces and they suggested the proper size copper gaskets which I will have to measure for. I'll also replace the valves in #3. So, some little projects - which I always wanted to learn anyway - and we'll be up and running again. Gotta' replace a couple bent pushrods too.

Mark M
Project: 64 Spyder Vert running 80 hp heads and carbs
1st Vair: 65 Corsa 140
St. Louis, MO
Show Me Corvair Club &
CORSA member

"If it's not broken, you're not driving it hard enough"

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Re: RAV was right, Compression, call me stupid & ?s
Posted by: Mark M ()
Date: February 21, 2009 04:40PM

Meant to say, valves in 1 and 5 are very good, 3 has the bad set.

Mark M
Project: 64 Spyder Vert running 80 hp heads and carbs
1st Vair: 65 Corsa 140
St. Louis, MO
Show Me Corvair Club &
CORSA member

"If it's not broken, you're not driving it hard enough"

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