I've been trying to nail down my vaccuum leak and was wondering how I would go about surfacing the manifold flanges? I've heard many guy here talk about doing it and how out of wack the manifold is before doing it. Is it something I can do at home or do I need to take it into a machine shop?

No. Just get a pack of 400 grit carborundum or similar sandpaper.

Place the sandpaper over a hard flat surface (like a piece of steel) and firmly rub the flange area over it in a random, circular or figure 8 motion until it comes smooth and flat.

The flanges are aluminum, so it shouldn't take much.

Ray

I have not done Road Star manifolds, but I have done plenty of VW bug manifolds in the day. If you bought Kadrons with aluminum manifolds, they were warped. I don't care what you say, every set came from the factory warped.

Anyhow. The easiest way to nail this at home is get a mirror or a piece of glass (glass is about as flat as you can get) put a piece of emery cloth on it and move the manifold flange gasket surface around in a circular motion. To check it, remove the emery cloth, clean the flange and gasket and put the flange on the glass. If it mates up, it is flat. If you still see areas where the flange doesn't hit the glass, more polishing.

I have a 5/8" thick x 4' x 7' glass table I surface the manifold on. Use painters or body masking tape to tape 400 grit carborundum paper to the glass and use some kind of oil on the paper. If you don't have any thin oil you can use olive oil. YES olive oil. Put it in the middle of your paper and hold the flange flat and work in a figure 8 cleaning the flange form time to time. You will notice that there is rubber on the flange that comes off first then there is a finish like varnish that will come off next. There will be dark area that show up with the varnish still on them those are the low spots. Keep cleaning and do the figure 8 until all spots are gone and the flange is shinny. Shine a light from under the glass and see if you can see any gaps between the glass and the flange if you can't your good to go.

Sorry guys don't mean to hijack this tread but is there a difference between a 1600 and 1700 intake manifold. I'd like to buy a used one on ebay to port and work the flange area but keep only seeing 1700's. Also how much work is involved in removing the manifold. Thanks.

I can't say for the compatibility for the manifolds, but as to what's involved to take off the manifold, here's my steps...

- Remove tank
- Remove air intake
- Disconnect fuel pump and enricher knob
- Remove carb
- Remove fuel pump
- Remove fuel pump bracket
- Remove manifold

Don't forget the carb heater and the TPS plugs on the left side of the back bone they are on the carb so you have to have them off before the carb comes off.

Ok, thanks..im sure its not to bad once the tank is off...

onebadd68 wrote:
Sorry guys don't mean to hijack this tread but is there a difference between a 1600 and 1700 intake manifold. I'd like to buy a used one on ebay to port and work the flange area but keep only seeing 1700's. Also how much work is involved in removing the manifold. Thanks.

Yes, there is. I have a nemesis alum. manifold made for a 1600 thats going on this winter and I tried it on when my NFG leaking stocker was giving me fits. I think all thats involved is to slot the bolt holes slightly and it should go. I felt around the inside and the ports lined up good. I don't know how much trouble you will have trying to seal the POS stocker if you try this.

Good luck, Coot

Since my surgery I've watched about every MC program I could. Almost feel I can do almost anything on a scoot now . Once the doc gives me a release date I plan on porting, new air filter and bracket as well as a few other minor things. Good thing I've got the reality here to fall back on.

GP