Non-doghouse to doghouse?

[Mesophus]

Hi, all,

I am replacing the heads on my first VW purchase since 1977. After a lot of reading, I decided to replace the heads on any VW engine that I could not verify the mileage on. Turned out the exhaust valves stand high, and both heads have cracks from exhaust valve to spark plug hole.
I would like to change the non-doghouse fan to a doghouse. When I removed the oil cooler, I found lock washers (@$^@!!!) being used as spacers under it. I need to know what I need to do to change this baby over to a doghouse. I have a doghouse that was on the rust bucket '70 beetle, along with bracket, thermostat, linkage, and everything but a couple of circlips and the return spring (have no idea where that went!).
After fitting up my rebuilt head I find the one side does not want to allow rocker arms. I seem to need to use the spacers I found on the original head on one side. The valve stems are sitting so high that the rocker arms themselves, not the adjusters, will be doing all the work.
This is for a '68 Transporter. I am hoping to get through October with this "mini rebuild", when I intend to build a new engine for it. Oh, yes, it's a 1600 SP.
Any suggestions on these issues welcome. I want this thing to be a dependable daily driver for just a few months. This engine will be rebuilt as a standby spare.

Off to school now.....

Thanks!!!

[Amskeptic]

After fitting up my rebuilt head I find the one side does not want to allow rocker arms. I seem to need to use the spacers I found on the original head on one side. The valve stems are sitting so high that the rocker arms themselves, not the adjusters, will be doing all the work.
This is for a '68 Transporter.

What you are describing is the classic Volkswagen FrankenEngine.
You must slow down and start measuring.
Measure the deck height. It must be the same on each side of the engine.
Measure the flycut in the heads, between the fin surface and the ledge where the cylinders contact the head. It must be the same on both sides of the engine even if you have to find spacers.
Measure the combustion chamber volumes. They must be identical.
Check your pistons for dish, and make sure they are the same.
You can calculate your compression ratios with an online calculator. Stock '68 bus wants 7.7:1 compression ratio. Dual port replacement engine with 8mm head studs might be the newer low-compression 7.3:1 ratio.
Rocker arm lengths need to be compared. After all of these measurements are equalized, THEN you can see about rocker stand shims to get your valve train geometry straight.
You can modify these measurements with barrel shims, head spacers and even machining in the combustion chambers or piston crowns. Optimal valve train geometery may require new pushrods if yours have been played with.
You need a sophisticated understanding to deal with FrankenEngines.
Colin

[Mesophus]

I got the rockers to fit OK, it just took a little more shuffling and adjusting. I just needed to step back and take a break.
The engine still seems a little Franken, though, as there is a roll pin-looking shim in one of the outboard oil cooler holes. The cooler had lock washers instead of the stock spacers (!!!). I scavenged 2 shims from a previous engine teardown (one of 5 that I paid $75 for).
What I am hoping to do is figure out how to replace the non-doghouse cooler with the doghouse I have. This I took off a '70 beetle that had a '73 DP engine. The original one on the bus had no thermostat, flaps or linkage. The doghouse I have for it has everything but the return spring and a few of the clips. Are there any fit/interference issues in a modification like this, or will it all pretty much go together?

Cheers

[karl]

I have never had luck making the connecting rod between the thermostat and the right side flap fit in and make the flap work correctly on the single port head.

The hole in the SP head is in a different position and the arm on the doghouse flap does not line up.

[bus71]

One thing to be aware of is oil cooler seals. If you have an early case, the holes will be 8mm. The doghouse will be 10mm. You can buy seals that are 8 on 1 side and 10 on the other. A doghouse cooler should fit fine. Good luck!

[karl]

One thing to be aware of is oil cooler seals. If you have an early case, the holes will be 8mm. The doghouse will be 10mm. You can buy seals that are 8 on 1 side and 10 on the other. A doghouse cooler should fit fine. Good luck!

http://www.oldvolkshome.com/oilcool.htm

[hambone]

I have never had luck making the connecting rod between the thermostat and the right side flap fit in and make the flap work correctly on the single port head.

The hole in the SP head is in a different position and the arm on the doghouse flap does not line up.

Hmmm interesting. Anyone else with this experience?

[Bookwus]

Hiya Bob,

Karl's experiences with aligning up the thermostat connecting rod were NOT what I experienced.

This is not to say that the whole fitting process went easily, but it did fit. I fit the flaps/connecting rod assembly without the fan shroud. This allowed me to get two important jobs done. Obviously fitting the connecting rod was one of those jobs and then adjusting the thermostat position/height so that it fully closed and opened the flaps.

Once that was done I marked the position of the thermostat and removed the flaps assembly. I then screwed it into the fan shroud, hooked up the flaps' connecting bar, and installed the fan shroud. That took a little doing but with some jiggling around, the connecting rod popped through right where it was supposed to.