Intake manifold pressure tester Motorcycle Tool Discuss Intake manifold pressure tester in the GOOD STUFF FOR CLASSIC MOTORCYCLE forums; Mike Beam (mbskeam), a member on this and a few other old bike forums, makes a tool you can use to check for leaks in the intake manifold. It consists ...

[Mark44]

Mike Beam (mbskeam), a member on this and a few other old bike forums, makes a tool you can use to check for leaks in the intake manifold. It consists of a plate with threaded holes for 3 or 4 bolt manifolds, some clear tubing, an adjustable pressure gauge that shuts off the pressure at the designated setting, and a fitting so you can hook it to a compressor.

To use it, you take the carb off, attach the plate to the intake manifold, and pressurize the system to about 10 -12 psi. When the system is pressurized, spray a soap-water solution on the joints in the manifold. If there's even the tiniest leak, lots of bubble foam appears at the site of the leak.

I bought one for my WL back in May or so, and just got around to using it, and found that my system wasn't leaking, but the last person who had the carb off put it back on with only one gasket instead of the three that you're supposed to use with the manifold extender. I paid Mike $35 for the unit, and consider it money well spent.

[Bigincher]

I have the utmost respect for Mike, and all his mechanical abilities and knowledge. He really knows his stuff, and is good with everything. He is doing a service to others by making this device available to others without the means with which to fashion their own.
However, since I already have a pressure reducing regulator, and just about all the other parts needed to assemble my own manifold pressure testing device, I made my own. I had to buy new air fittings, so I ended up with 6 bucks in it. If I counted my time, it would cost over $50.



Here it is fitted to the manifold with a test on it.



I didn't have any leaks either. It's reassuring to know you can rule that aspect out of the equation.

[panacea]

Since I've had no work lately I figured I'd do a test on my intake as well.I also made a test plate which bolts up to an S&S style manifold, and used a regulator set at about 15 lbs. I did find a leak at the rear nipple that screws into the head, so I removed the nipple, cut a new gasket out of gasket material, and srewed it back into the head with a little steam pipe sealant on the threads.I found the rubber "O" rings were really gummy and had been "munched" somewhat from the expansion and contraction of the manifold/nipple joint. When I was in Davenport I bought some of the Viton "O"rings from Cotton, so this was a good time to git 'er done. The main reason I suspected a manifold leak was the way she started right up when cold but was a real pain in the ass when hot. Hopefully cured now with no bubbles at all on the re-test...Mike

[mayanruben]

Very interesting, seems like its agood solution when all else is failing.. Congratulations on american ingenuity..
ruben

[Bigincher]

Actually, testing the intake tract for leaks is one of the FIRST things I look at. You have to rule out a leak before you can proceed, really.

[Sarge]

Originally Posted by panacea

...The main reason I suspected a manifold leak was the way she started right up when cold but was a real pain in the ass when hot. Hopefully cured now with no bubbles at all on the re-test...Mike

Mike, make sure that you check your point gap, if you're running points. That's also a symptom of points wearing and growing too close. Just advisin'.