Previous owner forgot to install head gaskets

[chopptrk]

Can you tell I've never been inside a vw engine? I searched the web stores for new head gaskets to have on hand when changing push rod tubes with no luck, then read somewhere that no head gaskets are used,,,ok,,cool. Sooo, what's the deal, just clean both sides and re-install? I'll also measure bore/stroke to verify engine size while heads are off. I'm guessing it would be a good time to check valve seats? Thanks

 

[rhino 2]

Can you tell I've never been inside a vw engine? I searched the web stores for new head gaskets to have on hand when changing push rod tubes with no luck, then read somewhere that no head gaskets are used,,,ok,,cool. Sooo, what's the deal, just clean both sides and re-install? I'll also measure bore/stroke to verify engine size while heads are off. I'm guessing it would be a good time to check valve seats? Thanks

No head gaskets are used........Its a medal to medal fit........Clean both sides but ''Do not scuff''....

 

[chopptrk]

Clean both sides but ''Do not scuff''....

Thanks Bob

 

[vwbug72501]

Here's 2 things to look for when heads are off:

1. Cracks between spark plug hole and valve port (common) or between intake and exhaust ports (less common).



2. evidence of compression leakage between head and jug. This picture is extreme. Usually discoloration and slight roughness at mating surfaces. This is caused by loose heads. usually indicative of head studs pulling out of cases. VW recommends checking head torque on a regular basis. This is also a picture of an extreme case.



Remember these engines are getting long in the tooth and fatigue is taking it's toll.

 

[rodekyll]

Good tips. If the heads are coming off you might as well service them. If you have extreme compression leakage you can get the head surface fly cut. Light blowby can be fixed by lapping the jug against the head. If you have an old big-stud case you can have case inserts installed to stop the studs from pulling. Replacement cases already have this done.

There were low compression heads made with a little step at the mating surface. When the step had to be removed during a fly cut we had spacer rings we inserted to dialthe compression back. They also acted as gaskets. So that might be an option too. An added benefit is that lower compression means less stress on the head studs. So they're less likely to keep pulling and continuing the vicious cycle.

 

[chopptrk]

Thanks for the good info guys. I took one of heads off Sunday and everything looked good, i'll be taking the other off this weekend. The bore and stroke was 85.5 X 69 which seems to be the 1600, however the push rod tubes are the shorter 7 1/16 length, used mostly on the 1200cc. Read that it could be because of "fly cutting", whatever that means. Head bolts are the smaller 8mm. Could this be a 1200 engine with 1600 jugs and pistons?

 

[DeathBySnuSnu]

Unlikely a 1200. Not that it can not be done......but that would be some serious machine work to make 1600 parts fit in a 1200 case. The vintage speed guys do it for history sake.

Pictures.

The push rod tubes are crush sleeves. They have to be un-crushed to use again.

Fly cutting heads can mean a couple different things. In your case they are talking about what is called in the v8 world "shaving the heads". Machining to increase compression. Again unlikely unless it has a huge cam and dual carbs.

Pictures

 

[chopptrk]

Rex, the push rod tubes that I had ordered for a 1600 were 1/2 inch too long. It didn't seem like they would crush 1/2 in without damaging them, so I ordered the shorter tubes which are 1/2 in shorter (for 1200cc). I haven't received them yet. Am I missing something here? Do the longer tubes crush 1/2 inch when installing heads? I plan on using the shorter tubes when they arrive, un-crush them 2mm as per instructions, then install. This sound right? Thanks

 

[DeathBySnuSnu]

Entirely possible.

It has been a whole bunch of years since I have had a stock width engine.

I had to measure the gap between the ruffles and add them up.

Mine only have ruffles on one end and what I remember is .300" crush.

 

[chopptrk]

Shorter tubes came in today and worked great. While waiting this morning I pulled off one of the cylinders to check rings, looked real good, piston & rings looked fairly new. Slapped it back together and continuing the wait for the back-ordered carbs.

Also, checked the case number, "F 10 05 09X" The info I found said it was a 1300, trike title says 1969. Piston size and stroke says 1600.

 

[DeathBySnuSnu]

A 1300 is an H case.

Dont know what a F case is....not in the list.

Are you sure there is not an A in front of that? That would be a 1600 single port.

Usually an extra stamped at the end like that X, means a remanufactured engine.

Some remanufactured ones are re-stamped with a complete NON VW numbers.

Is it a dual relief case?

Dog house oil cooler?

It is entirely possible that you were sent some extra long stroker motor tubes by mistake.

 

[chopptrk]

Finally got a pic up, just gotta turn your head sideways. It's a dual relief case. Also I noticed the "re-manufactured" stamp before the numbers, and there's a A and P where the case splits.

Aircooled website says 7 1/2" tubes for 1300-1600,,, and 7 1/16 for 1200.. Don't know why but my engine/heads took the shorter 7 1/16.

 

[DeathBySnuSnu]

Yep.

Original number has been machined off and a different number stamped.

But if it is dual relief....then it is the latter 1600 case.

But if the other tubes fit and work.....then that is all that matters.

 

[DeathBySnuSnu]

As a side note.....

Replacement engines used to not have the serial number stamped.

The installer was supposed to stamp the original engine number onto the replacement.

So there are lots of engines out there with 1200 or other older serial numbers stamped into newer replacement 1600's.

For instance....my case was not stamped, the DMV wanted the number transferred onto it......soooooo my engine serial number is a 1985 gl1200 Honda like my fork neck. So as far as the DMV cares it is a numbers matching 85 wing with a trike conversion.

 

[chopptrk]

Good deal, hell i'm just glad to know what size engine, instead of saying I "think" it's a 1600. And seems it was re-built not too long ago from the looks of the heads and pistons. The previous owner did say it was a fresh re-build, guess he was being honest, lol, he's actually a preacher.:Angel:



Good riding weather this weekend, gonna have to jump on the two wheeler to get my "fix"

Thanks for the info Rex

 

[rodekyll]

Replacement cases had 8mm head studs and a blank area under the generator tower to stamp in the old engine number. They were also "universal" cases. They had the drilled castings to attach the type III rear mount.

Im nervous about the push rod tube situation. I don't recall the proper compressed length of the push rod tubes, but I too think 1600's were longer than 1200's. They need to be under a lot of squish to seal. Your old ones are probably still compressed. How long are they? How long are the push rods? You remembered to rotate the seams upward, right?

For normal street engines, fly cutting cleans up the head-to-cyl mating surface. It is done in thousanths. For performance the shoulder that makes the mating surface is taken down in hundreths to increase compression. Although they move the head closer to center, neither operation would take so much that the push rod tubes would be affected.

 

[grandpanystrom61]

Okay, never have taken a bug engine apart before, not taken a head off yet, so I should not speak.

I am lost, all signs say it is a Re manufactured 1600 dual port case, but yet it will only take the 1200 size tubes?

So this would mean you have a shorter stroke, shorter push rods to pistons with shorter cylinder walls than what a stock 1600 would have ? I just pray that my engine is not this confusing, better yet I just pray I do not have to rebuild it, ever.

 

[rodekyll]

On the face of it, it doesn't make sense. I'd have to see it.

 

[chopptrk]

Im nervous about the push rod tube situation. I don't recall the proper compressed length of the push rod tubes, but I too think 1600's were longer than 1200's. They need to be under a lot of squish to seal. Your old ones are probably still compressed. How long are they? How long are the push rods? You remembered to rotate the seams upward, right?

Ok, been doing a lot of reading while waiting for parts. I became aware that the tins under the cylinders (between cylinders and push rod tubes) were missing. I read that they were needed to help cool enging, so I ordered them. Then noticed I would have to remove the push rod tubes to install them. Dang it,, removed the heads, again.

Soooo, after removing the tubes, I started thinking about what rodekyll said about length of old tubes. I started going through the trash can and found an old tube, it was the longer length made for a 1600. Damn it. Installed the new longer tubes and all is well. I didn't think the tubes would compress as much as they did, but they did. Thanks for the help guys.

I also received the twin carb set-up that I've been waiting on. Got everything (tins,tubes,carbs) installed yesterday. All went good. The trike has never ran so good. Went for a ride and noticed more power for sure. Aircooled.net did a great job going through carbs adjusting and setting, I didn't have to adjust anything. I got the linkage right and all was good after that. Checked with syncrometer and they were perfect, think I got lucky? ha

Just wanted to thank all that helped me out, nice to hear from people that know.