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Mon Nov 09, 2009 5:38 pm

Desertbusman wrote:
fusername wrote: I really think that the pushrods simply are not in the cup in the lifter. No! Go grab a lifter and a pushrod and try to simulate it. You can't. If a pushrod was hung up on the end of a lifter the pushrod would be out about 5/8". You wouldn't be able to even get the rocker arm assembly installed.

I am familiar with the thicker foot lifters, they do not affect geometry that much. Doesn't affect geometry at all.

if its not clear, DBM wrote all the stuff in bold, to speak directly to my post. I actually prefer responses written that way, nice and simple to follow.

gonna say you are wrong on the not being able to assemble it wrong. if that were the case I wouldn't have done it three times in the last month, once on a vanagon and twice on a porsche 914. he sayss he can't get the rocker to stop opening the valve, even if the adjuster is removed from teh rocker, atleast the way I understand it. as to the big foot lifters not affecting geometry, I am aware they .shouldn't. but since I didn't know difinitivly, i erred on the safe side to say the effect should be minimal, not enough that yo uwould notice it by eye on assembly, only whilst setting geometry. however I can't guraentee any of that. I do know that I have assemebled engines using those lifters w/ minimal geometry problems.

out of curiousity, how much did the old wrong seals hold the rocker amrs up? In my mind I am seeing those thigns as being ~1/4 inch tall tops, can't bvelive it would make that much a difference, esp after being compressed. I could be wrong though.

Mon Nov 09, 2009 5:48 pm

Desertbusman wrote: josh wrote: Using shims is one way to adjust. But in your case I don't think it will be enough to do it right. You probably need shorter push rods.

This adjustment is almost always done with the engine out of the car.

Yes, good geometry is real important.
Spacers and special length pushrods go along with non stock and performance parts. And pretty much needed with swivel adjusters. If he is stock the problem is elsewhere. Spacers would not be needed.
Yes, builders set the geometry when building the engine. But it can sure be done while in the car. Only deal is laying on your back :lol: .

Stock on a 40 year old motor is a relative term. He has already stated that his lifters are apparently non-stock. He is using non-stock copper head gaskets. It sounds like his valve stem heights are suspected to be non-stock.

Some of these items may have their own problems. But if he's not going to tear down the engine again, he could at least compensate by getting the rocker geometry right.

Mon Nov 09, 2009 6:14 pm

fusername wrote:
gonna say you are wrong on the not being able to assemble it wrong. if that were the case I wouldn't have done it three times in the last month, once on a vanagon and twice on a porsche 914.

But our OP has a T-1. When you first mentioned it I went a grabbed a lifter and pushrod. If the PR enters the lifter it goes all the way into the socket. I've never touched VW engines other than T-1's. So thanks to your warning I'd now know what to watch out for if I ever get past T-1's (no, never :shock: ).

Mon Nov 09, 2009 6:20 pm

Yep, hung up a few PR's on type 4's but can't say it's ever happened on a type 1 and not been obvious.

Mon Nov 09, 2009 9:02 pm

fusername wrote:
out of curiousity, how much did the old wrong seals hold the rocker amrs up? In my mind I am seeing those thigns as being ~1/4 inch tall tops, can't bvelive it would make that much a difference, esp after being compressed. I could be wrong though.

Maybe 1/4"... minus however deep the indentation is. It's definately enough to make a difference. And I agree with the others about the lifters, they are shaped such that if you push the pushrod into them at all, they will gravitate to the center.

josh wrote: Stock on a 40 year old motor is a relative term. He has already stated that his lifters are apparently non-stock. He is using non-stock copper head gaskets. It sounds like his valve stem heights are suspected to be non-stock.

Regarding the copper gaskets, I took them out of the engine, so I put them back in. I have read some stuff since then about how vw stopped using them in new engines, and they're not necessary, but the engine ran fine for a long time with them before, so I guess I'm not too worried about it. Also, the cam followers are new, but I bought them with the idea that they were stock. They are probably not far off enough from stock to make a difference.

I am familiar with the concept of rocker arm geometry, and I realized that it was related to the issue I am having. The geometry is so far off, that I can remove the studs completely from the rocker arms, and still not be able to fit a feeler gauge in there.

I am a little concerned about what could be causing it to be so far off. I ordered the book already, and will look through it as soon as it gets here. If it turns out I can't find anything that I have messed up on, then we can assume it was probably the rebuilt heads causing this? And assuming it is the heads, the thing to do would be to use shorter pushrods or shims to correct the geometry? Can anyone give me advice on different than stock pushrods in case this turns out to be the thing to do?
Thanks.

Mon Nov 09, 2009 10:09 pm

Push rods get custom cut and assembled based on using an adjustable pushrod to determine the length for good geometry. There is a great topic on this in the engine/performance forum.

With your final bold conclusion, consider this. If the heads were machined to fit farther down on the cylinders the C/R could be about anything. It should have been all worked out. CC'ing the heads and all that. If the valves are wierd and somehow sticking farther out of the backside of the head that would affect the springs pressure. There might be some kind of legit reason for all this but going spacers or different pushrods at this point might not be the cool thing to do.
You have a very interesting situation.

Mon Nov 09, 2009 10:46 pm

Desertbusman wrote: If the heads were machined to fit farther down on the cylinders the C/R could be about anything. It should have been all worked out. CC'ing the heads and all that. If the valves are wierd and somehow sticking farther out of the backside of the head that would affect the springs pressure. There might be some kind of legit reason for all this but going spacers or different pushrods at this point might not be the cool thing to do.
You have a very interesting situation.

So what would the implications of this be? I've never gotten into any heads and pretty much trusted this guy to know what he was doing. If it turns out not to have been something I did wrong during assembly, would I be able to do anything about it, short of taking it back to a machine shop and paying someone who knows what they're doing to deal with it?

Obviously, I would rather not tear down the engine again, but I would much less rather break down in the middle of texas or some such horrible thing...

After all this work, I really don't want to just half ass this at the very end and have it turn into a more major deal than necessary, but it is extremely important that I be in Tahoe before the snow starts to accumulate.

Mon Nov 09, 2009 11:31 pm

I have a possible solution that will elminate one item. Can you locate someone near you who has a stock VW pushrod for that engine and see if it makes any differnece. Could thos pushrods be a custom length with the PO setting them tight to begin with?

Also - did you replace just the lifters or the cam too?

Another way out there possibility whether the cam was replaced or not is that the base circle is larger. If it is the same cam could it be the old lifters were ground to allow a larger base circle? This is not a standard practice but it would lower the ramp speed as a percentage on a higher lift cam.

Tue Nov 10, 2009 12:09 am

Uvula wrote: I've never gotten into any heads and pretty much trusted this guy to know what he was doing. If it turns out not to have been something I did wrong during assembly, would I be able to do anything about it, It possibly might just need a deck height adjustment. Wait for your book :lol:
Somewhere ??? there are measurements for how high the valves and springs are above the head. If the head guy did something you are not aware of it would either be in the combustion chamber/mating flange area or the valve spring area.
Answer Kent with his cam question. New cam? Howard Washington has been able to convince some of the cam manufacturers of the value of a LBC large base circle cam design. And evidently some are being produced. That would solve the mystery.
Pushrods longer than stock would cause it but you have the same ones as before?

Right, you might just do spacers and go for it. But, like you say, you don't want any potential reason to break down in Texas or anywhere else. Snow in Tahoe comes and goes every year and so do a lot of peoples engines. Can't stop snow but engines should last a long time.

Tue Nov 10, 2009 7:41 am

i assume the possiblity of a fly cutt after the heads were rebuilt has been discussesed. I am just going to chime in if everything else checks out and its just geometry issue (say big flycutt offset by chamber work) you could get pushrods for a 2.1 or typ4, they are shorter, some by very little.

Wed Nov 11, 2009 10:12 am

SGKent wrote: I have a possible solution that will elminate one item. Can you locate someone near you who has a stock VW pushrod for that engine and see if it makes any differnece. Could thos pushrods be a custom length with the PO setting them tight to begin with?

Also - did you replace just the lifters or the cam too?

Another way out there possibility whether the cam was replaced or not is that the base circle is larger. If it is the same cam could it be the old lifters were ground to allow a larger base circle? This is not a standard practice but it would lower the ramp speed as a percentage on a higher lift cam.

The cam is the one that was there before. and the pushrods are too. The only other vw around here that I can take pieces off is a dune buggy that I'm guessing is less likely to have stock parts than the bus.

I don't think the cam is a different than stock one, with reground lifters, but I guess anything's possible. Seems unlikely to me though.

Even if the pushrods have been longer than stock all this time, I'm not seeing a reason for it to be a problem now, when it wasn't before. Is there a possibility that the new pistons/cylinders could be causing the difference? 'cause other than that, the only things different are the lifters and the heads.

Still waiting for the book to come...

Wed Nov 11, 2009 11:21 am

Desertbusman wrote:
Somewhere ??? there are measurements for how high the valves and springs are above the head.

I'm guessing you mean somewhere in the book I'm waiting for, right? I looked in the bently and could find no such measurement.

After reading these posts I decided to go out and see if I could find any more information without taking heads off, and I noticed that the valves are not all the same distance from the heads. I can actually just barely fit my .006" feeler gauge under #3 intake when the stud is screwed all the way out. Does anyone know how little variation there is supposed to be?

Wed Nov 11, 2009 11:33 am

pretty much anything that changes the valve geometry is cause for cutting new pushrods, whether it be a different thickness of lifter, different cam, altered deck height by using shims below the pistons, different height pistons, not running head gaskets, flycut heads, or even deeper seated valves.

It's supposed to be very critical, valve geometry. The factor that you need to change is the shim below the rocker. Get that right using an adjustable pushrod so that you're getting about advertised lift (and your valve is still closing).

I've found when doing this that rockers hitting the head cover is the limiting factor. You want to make sure you've got .030-.049 inch clearance everywhere.

Wed Nov 11, 2009 3:50 pm

Uvula wrote: I noticed that the valves are not all the same distance from the heads.
Rockers are apt to vary. You can really only check it with the rocker arm assembly removed and laying a straightedge across the 4 valve ends. Maybe someone in the Engine/Performance forum can give a dimension for how high above the head they should be. Did he put in new valves?
Same cam, pushrods, rockers, heads, different cylinders, lifters, and maybe valves. The question is if your engine isn't as wide as it used to be. The concern with that would be if that variation was in the combustion chamber volumes. As far as valve geometry that's a seperate topic. When everything is stock there isn't a problem.

Thu Nov 12, 2009 11:36 am

So if I were to measure the deck height, and find it good, then there would be no problem?

Thu Nov 12, 2009 4:37 pm

Wait for the book :lol: You would want to also CC the heads to know how to dial in the C/R if necessary. After that you would be able just do whatever is needed to set the valve geometry.

Sat Nov 14, 2009 1:57 am

-New discovery-

Was looking in Wilson's book for some non-related info and he mentions that early 40 HP engines had shorter lifters that also had a shorter flange at the head. To compensate for the length they used longer pushrods. And all the shorter lifters have pretty much been eliminated from reusing.

So if you did have the old 40 HP lifters and long pushrods and then used the correct lifters and your old pushrods that answers your question of why.
Compare one of your old lifters with one the same as your new ones. And if that was the difference you could throw in a set of new, correct for a 1600, pushrods. Valve gap problem solved.
You still would be good to pull the heads and do the proper setups. Your new barrels, new pistons, not knowing how it was built before with the head shims, maybe head work, could now have produced any kind of a compression ratio combo. That's a real important part of a engine build.