Water pump Housing to Manifold clearance.

[DMT]

I am refitting my intake manifold. After following instructions from Richard and others I have dry fitted it with just gaskets, no washers. All bolts now travel all the way in finger tight. I have tried a 0.05mm feeler and seem to have no gaps either side of all gaskets.

I have checked and I think the water pump housing is just touching the manifold. I cannot get a very thin strip of flexible plastic between the two.

I cannot see an obvious high point.

Is there a recommended method to find the high spot and file it down.

Cheers

Dave

[Lingen]

Dave.
If it is touching, you could slide the manifold back and forth along the vee making it hit the water pump cover. Do this a few times with a good push, and that should leave register marks on both castings. There is plenty of "Meat" on either of them to get busy with a surform plane to gain a clearance.
Mike.

[DMT]

Thanks Mike.

How much clearance would be OK? If I get minimal clearance with no gaskets would fitting gaskets give enough clearance when tightened down?

Dave

[richardthestag]

Hi Dave you mentioned in the first post that you fitted WITH gaskets and it is touching, and then in the post above "no gaskets".

Ideally you would not want it touching

[DMT]

Hi Richard, a bit unclear, sorry. It was just touching with gaskets. I have filed it to a condition I can just pull a very thin plastic sheet between the pump and manifold without gaskets. With the gaskets fitted would they give enough clearance when tightening the manifold down?
Dave

[jbuckl]

Hi Richard, a bit unclear, sorry. It was just touching with gaskets. I have filed it to a condition I can just pull a very thin plastic sheet between the pump and manifold. With the gaskets fitted would they give enough clearance when tightening the manifold down?
Dave

In design , for static cast to cast clearances we target 3mm.
As you know the parts, target 1.5 after fettling.
Remove material from both parts.
Use bluetac to help.

[DMT]

Cheers Julian. I might have to dig out the plasticine from my old school days!!
Dave

[richardthestag]

Hi Richard, a bit unclear, sorry. It was just touching with gaskets. I have filed it to a condition I can just pull a very thin plastic sheet between the pump and manifold without gaskets. With the gaskets fitted would they give enough clearance when tightening the manifold down?
Dave

So if the shimmed water pump cover if fixed, that becomes your start point..

Next drop the inlet into place with gaskets, is there a gap? Yes! then no worries. However if there is no gap because of head skim etc then revert to Julian's suggestion above. Belt sanders are very useful to adjust tolerances on casting excesses

[MikeParker]

The important clearance is the top of the vanes to the pump cover. It should be about 1 to 1.5mm. The method of using the top of the pump retaining bolt-to-cover does not work for many pump/cover combinations. Ultimately, it is not that clearance that matters. To measure the vane-to-cover clearance use blu-tac or 1mm shims over the vanes (e.g. card). IMHO it is this clearance that makes most difference to the Stag's cooling performance.

Mike

[DMT]

Thanks Mike, not a problem for me. The vane was removed and plug fitted as I have a Stag-Dad external pump.