Corvair DiagramCorvair Photo
Corvair Center
home forum corvairs calendar links Corvair Podcast
California Corvairs
Clarks Corvair



Chevy Corvair License Plate
Chevy Corvair Chrome Wheel
Corvair Center Forum :  Corvair Center Phorum The fastest message board... ever.
Corvair Center 
Pages: Previous123
Current Page: 3 of 3
Re: Re-ring an engine
Posted by: Zodi Davis ()
Date: February 23, 2012 11:06PM

All things being equal, If the engine has never been apart all parts have worn in unision.
As stated earlier usually if you seal up the valve wear for example new guides and valves that are worn past service limit it puts more pressure on the rings causing the already worn rings to "dig" in to the cylinder bore escalating wear.

offer still stands, If you don't have a ridge reamer and ball hone I'll gladly send out a loaner, Other than a set of cast rings you are already replacing head gaskets taking the heads off so not a whole lot of additional expense to seal up the other side.

J.M.O. Regards, Greg/Zodi davis

Greg/Zodi Davis
Sierra Vista, AZ.
65" Monza convertible
65"Corsa turbo coupe
66" Corsa coupe 140
66" Monza 140
65"Corsa convertible
62" Rampside
64" corvan
64"Greenbriar deluxe

Options: ReplyQuote
Re: Re-ring an engine
Posted by: brocklanders ()
Date: February 26, 2012 02:57AM

Well yesterday was the big day, and me and Ed had some decent luck. We removed teh heads after soaking the rusty head nuts with PB and Naval Jelly (thanks Junky!) with a combination special socket for rounded nuts, and a 14 metric socket all nuts were removed. About 4 studs started to spin, but the vice grip trick worked wonders. After dropping the engine, the heads came off without incident. after checking lots of measurement with snap gauges for taper, and out of round, we decided a simple re-hone, ridge ream and re-ring was a cheap project since we were right into it already. The cylinders were marked, and removed again with ease. There was a very light score in # 6 cylinder, but it's believed a ball hone should be sufficient.

Measurements:
Ed measured each cylinder with a snap or telescoping gauge at the top and bottom of each cylinder, in opposite directions at both top and bottom. there was no out of roundness detected, so the measurements are simply the bottom and top bore of each cylinder.


#1: Top: 3.438 Bottom 3.437
#2 Top: 3.44 Bottom 3.44
#3: Top: 3.434 Bottom 3.433
#4: Top: 3.43 Bottom 3.43
#5: Top: 3.435 Bottom 3.435
#6: Top: 3.435 Bottom 3.435

We also measured the head gasket surface to ridge in combustion chamber to see if the heads had been shaved at some point. The measurement for all 6 were either .052- .053. We were informed the stock measurements should be between .050 to .055, so that should be telling use these are stock.


Here's the pics of the tear down:










1968 500 coupe 110 pg
1967 Fitch Sprint 4 door
Bowmanville, Ontario, Canada

Options: ReplyQuote
Re: Re-ring an engine
Posted by: brocklanders ()
Date: February 26, 2012 03:03AM













I realized later that we got the wrong numbers for the heads, but we did get that both heads had a 49 T1 on each and an ME and MC on either and a 32a on one and a 32B on another.

I'll get the right numbers Monday. But other than getting new rings, head gaskets, cyl. base gaskets pushrod vtube o-ring vitons (they were fine, I destroyed them removing them the wrong way sad smiley ) is that enough? Do I need STD rings, and one set of head gaskets or two?


1968 500 coupe 110 pg
1967 Fitch Sprint 4 door
Bowmanville, Ontario, Canada

Options: ReplyQuote
Re: Re-ring an engine
Posted by: MattNall ()
Date: February 26, 2012 03:15AM

1 You need to measure the cylinder ..but if the pistons do not have a "10" or "20", etc... most likely standard..


And YES double the head gaskets...

Open chambered heads are known for pinging...

Don't fall into the "while I'm at it" rut!

Ridge ream., hone, clean ring grooves with broken piston ring with one end taped to save your skin


Re-assemble

=====================================


Heads.... push the valve open and look for carbon on the BACK side of the valve.. [ valve guides or VG seals bad]

Then pour a solvent down the intake port and see if any of the intakes leak
[ a slow weep is fine! ]

Then in each exhaust port for them.





MODERATOR
Somewhere between Sea Mountain and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
.............................PG...................................Turbo

Options: ReplyQuote
Re: Re-ring an engine
Posted by: brocklanders ()
Date: February 26, 2012 03:15AM

Edit: head gasket surface to ridge in combustion chamber was .52 - .53 not .052- .053


1968 500 coupe 110 pg
1967 Fitch Sprint 4 door
Bowmanville, Ontario, Canada

Options: ReplyQuote
Re: Re-ring an engine
Posted by: MattNall ()
Date: February 26, 2012 03:28AM

1/2 of an inch? 500 mm??





MODERATOR
Somewhere between Sea Mountain and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
.............................PG...................................Turbo

Options: ReplyQuote
Re: Re-ring an engine
Posted by: malibusled ()
Date: February 26, 2012 03:33AM

1/2 inch Matt

Ed Bartlett
1961 Corvair 95 Rampside 110 4 Speed
1964 Corvair Monza Convertible 95 PG
1965 Corvair Monza Coupe 140/4 Speed Conversion - Oshawa Built
1966 Corvair Corsa Convertible 180 Turbo - Oshawa Built
Bobcaygeon, ON Canada

Options: ReplyQuote
Re: Re-ring an engine
Posted by: MattNall ()
Date: February 26, 2012 03:56AM

Wait for one of the experts to look at the head pics.. and see what they think.





MODERATOR
Somewhere between Sea Mountain and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
.............................PG...................................Turbo

Options: ReplyQuote
Re: Re-ring an engine
Posted by: Richard ()
Date: February 26, 2012 05:13AM

That isn't what anyone was talking about. That clearance is only important if the head gasket surface is milled so that the head doesn't sit down on the cylinder fins.

That is an open chamber head. You do not have any quench area that was being discussed.

I am not seeing anything that warranted taking that engine apart. I am back to the unanswered question about whether or not you checked your compression gauge against another one.







Edited 3 time(s). Last edit at 02/26/2012 05:17AM by Richard.

Options: ReplyQuote
Re: Re-ring an engine
Posted by: Brizo ()
Date: February 26, 2012 06:00AM

Brocklanders, You didnt mention what you found to explain all the oil,carbon and detonation--worn out rings? stuck rings? broken rings? bad valve seals/guides? It looks like those spark plugs are too short ?

Dan Brizendine,
'64 8door Greenbrier 140 PG. "In beautiful Wanamaker Indiana...with one stop light and 5 pizza shops"

Options: ReplyQuote
Re: Re-ring an engine
Posted by: MattNall ()
Date: February 26, 2012 06:24AM

Dan... threads are clean.... I'll bet the plugs are just filling the holes..


The Wet oil is just the sign of totally worn rings... seen it many times...

Throw a set of Cheap Cast iron rings in after just Ball honing the barrels to break glaze...

Drive on!





MODERATOR
Somewhere between Sea Mountain and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
.............................PG...................................Turbo

Options: ReplyQuote
Re: Re-ring an engine
Posted by: brocklanders ()
Date: February 26, 2012 06:27AM

Nothing. I have no idea where the oil came from. I was asked to remove the heads, and post the results. Heads were removed and sat on a bench, and questions were going to be asked here.

A quick once over all the pistons and rings showed nothing out of the ordinary. EVERY SINGLE cylinder had oil in it, and the pictures should show the amount of carbon in all the combustion chambers.

The plugs are NGK B7HS, recommended plugs for our cars, just on the cold end of the heat range (trying to fix pinging) Read the thread, I tried to determine the health of the rings and got tons of back and forth info that pretty much didn't help me.

Richard: I used only the one compression tester, and I understand your argument that they may be false readings, but my logic dictated that I have a massive pinging issue, I have oil in my cylinders, my engine was half torn apart and I cannot remove that oil to get a proper dry reading with another tester...I was urged to remove the heads and post the results.

Please realize that I'm new to this still especially this deep into the engine. I'm very much going on what I read here and it's a little disheartening when I follow 50 % of the people that urge me to remove the heads, then the other 50% tell me it's something different. The engine is getting re-ringed, the heads are VERY likely going to the machine shop for a cleanup. I ordered two sets of head gaskets, STD rings and cyl. base gaskets. The cylinders are getting ball honed and ridge reamed and put back together in hopes that ANY crazy issue that this could be will be solved, and I will get many more years out of the engine. Ask me anything else, I need any help that's offered.

thanks


1968 500 coupe 110 pg
1967 Fitch Sprint 4 door
Bowmanville, Ontario, Canada

Options: ReplyQuote
Re: Re-ring an engine
Posted by: 62corvairjunky ()
Date: February 26, 2012 06:38AM

Rings are the culpret IMO.


Clean pistons
Break glaze
Cast rings
.042 or .052 head gaskets.
Inspect heads
Put it together.thumbs up

Junky
Hurricane Utah.
Home of the "Red Desert Corvair Sanctuary."

 photo 7121255b-53ac-4335-a3ba-83724bf6f396_zps111b404a.jpg

62 Rusty Rampy
62 wagon under construction.(Taking all my time and $$)
61 lakewood parts car.
63 coupe
half a dozen parts cars n trucks
20x40 garage full of greasy parts

Options: ReplyQuote
Re: Re-ring an engine
Posted by: Tom Z ()
Date: February 26, 2012 12:15PM

..my first read on this because I *cringe* when people want to throw new parts in without first measuring things,BUT..Matt said to look at the backside of the valves for carbon build-up,which hasn't been done as yet; Where were all the ring end-gaps on each piston?-compression ring gaps at the bottom,5-7 o'clock? oil rail gaps not at 10 and 2 o'clock? How much 'out of round' are the cyl's? Piston to cyl clearance means the piston will cock on the wrist pin to some degree,and wear the cyl egg or oval shaped-so just putting new (round) rings in,without MEASURING the cyl's bore is a waste of time and $$..as to the front main oil leak,yes it would leak the better part of a qt in a 200mi run,,also remember that filling the oil to the 'full' mark also puts the oil level near the cyl walls,which can overload the cyl's when cornering,and promote oil entering past the rings..the 0708 smog heads are the biggest problem with the 'pinging' problem,either swap 65-67 non smog heads on or have yours 'made' into them by weld-up/machining..since your engine has been 'pinging' for a long time now,replacing the pistons at this time would be wise also from what I've read recently on FV (lengthy topic..)

Tom Z,,Rochester NY


Options: ReplyQuote
Re: Re-ring an engine
Posted by: malibusled ()
Date: February 26, 2012 01:26PM

Tom, we DID measure the bore, as Kyle previously posted;

#1: Top: 3.438 Bottom 3.437
#2 Top: 3.44 Bottom 3.44
#3: Top: 3.434 Bottom 3.433
#4: Top: 3.43 Bottom 3.43
#5: Top: 3.435 Bottom 3.435
#6: Top: 3.435 Bottom 3.435

I rotated the round edge snap gauges around in the cylinders and felt no tight or loose spots and we took many measurements through out the full bore of all the cylinders BEFORE we removed them, and determined that they are not out of round.

I did not note the exact clock position of the rings, however I did note that the gaps were NOT all lined up and seemed to be opposing eachother.

We believe this engine has not been apart before.

When we removed the heads (as recommended) and saw the massive amounts of oil, that is when we decided to pull the cylinders. I feel the cylinders are good for re-use.

Richard - As for measuring the gasket surface to head deck surface. That was recommended to us through a local well respected corvair guru, that works on alot of local Corsa members cars including mine. We were trying to determine exactly what you said "That clearance is only important if the head gasket surface is milled ". We were trying to see if the heads had been machined which would increase the compression ratio, which would contribute to the high compression readings and the pinging.

This car is at Kyle's work, about 45 min from his home, it's not really easy for him to just run out the garage and take more pictures or do more tests. I'm sure when he is back at work, he will inspect the heads more thoroughly before the final decision on sending them out, or re-installing as is.

Ed Bartlett
1961 Corvair 95 Rampside 110 4 Speed
1964 Corvair Monza Convertible 95 PG
1965 Corvair Monza Coupe 140/4 Speed Conversion - Oshawa Built
1966 Corvair Corsa Convertible 180 Turbo - Oshawa Built
Bobcaygeon, ON Canada

Options: ReplyQuote
Re: Re-ring an engine
Posted by: brentc ()
Date: February 26, 2012 10:17PM

Well, lets summarize what we do know and whats left to be established while you can look at everything- gotta get this back together;-)

Its a likely original GM 110HP '68 engine, with domed pistons and open chamber heads as it should be, and theres a lot of oil in the cylinders, which likely is the source of the pinging....the carbon is minimal, looks fine.

Where's the oil coming from?

-overfilled from wrong/miscalibrated dipstick
-drawn in via PCV system (missing/failed baffle)
-Vacuum modulator line (if Powerglide)
-sticking/worn out oil control rings

The engine doesnt seem very worn at all and I am not entirely comfortable with the oil ring idea- its reasonable but rare on an otherwise good compression engine, I would examine all potential other sources of oil, just toi rule them out. Pull that top cover and see whats in there.

The heads dont really look like they need any work, with the good compression you had, doing any work would be optional, unless theres a specific issue you find like a worn out guide.

You will be stuck with using open chamber heads, the other styles wont fit with the domed pistons. The pinginf likely has cracked the pistons around the ring lands and piston pins- you'll need to examine the ones you can get a view of to see if this has happened. It likely has, and that means the pistons will be weak and at elevated risk of failure. If this is the case, I would find another set of late rods and get cylinder kits from a vendor, have the rods resized and new bolts, and pressed onto the new pistons. This is not especially expensive, and you'll have essentially a 'new engine'. If you replace the pistons you can use flat top pistons and any style head you like, which might be advantageous for you later.

If you go the cyl kits route, get them with moly rings, which are the best. Thats also whats likely in there now, I think AIR engines all used them. IF the pistons you have now are satisfatory, use cast iron rings, these have the shortest lifespan of them all but are satisfatory for a rering, the rest of the engine will be worn out too by the time new cast rings start to let go again.

The ball deglazers dont do as even a job as the hones with the shoes on them, if you can get access to one. The crucial thing is that the finish is correct to get the new rings seated quick, get some advice or help from someone who does this a lot if you can.

One possible attractive option is GM cylinder kits- GM carried these until very late (about 1990 in Canada) for domed piston engines, theres were tons of them around, and they only fit 95-110's with open chamber heads, which are quite a rare bird. Consequently theres a fair number of these kits still around, new moly rings and all- you might luck out and find 6 for a reasonable price, they're not much value because for any other engine you have to throw away the pistons and get flat tops and people are reluctant to do that.

Keep your focus on getting this engine together or in three weeks you'll be eyeing the 140 in the sprint and end up with a bunch of disassembled Corvairs;-)

If the pistons are cracked and you are really on a tight budget you might be able to get some used decent condition factory flattop pistons from someone here, but they'll have to be measured carefully and the rod end size checked carefully too.

I would suggest doing two things to help determine whats next in summation;

- establish where that oils coming from with more precision
- Examine the pistons around the pin bosses and skirts for cracking

Keep going, you're making good progress;-)
Brent

Options: ReplyQuote
Re: Re-ring an engine
Posted by: Tom Z ()
Date: February 27, 2012 01:36PM

..AFAIK,the 'smog-95" pistons are 'flat-top',like all stock '64-up 164" ers,the 'smog-110' engines got the 'dome' to raise compression..used my magnifier on pics above,they look like flat-tops,correct for the smog-95hp engine..if ring-seal is the problem,the 'right way' to fix it is to have the cyl's *bored* first then get pistons and rings fitted to them;a shop that does VW/cycle engines that holds the cyl properly (torqued),then *hones* the surface finish will be best..buying/ exchanging units as Brent mentioned is the quickest way..

Tom Z,,Rochester NY


Options: ReplyQuote
Pages: Previous123
Current Page: 3 of 3


Sorry, only registered users may post in this forum.
This forum powered by Phorum.