The Ford Barn

cjc56 · 10-15-2014, 06:43 AM

I am looking for a vac leak in my 56 Tbird. The last thing to test was the wiper motor. I found that the motor (when in the off position) does not hold a vacuum. I would think that that means it is leaking when in the off position. Is anyone familiar when these motors and is it normal to leak in the off position. I have 2 of these motors which I have tested and both act the same way. They work great otherwise.

RCM · 10-15-2014, 08:21 AM

I believe they are suposed to leak. I disassembled mine recently, having never done such thing, and there is a part on its back, after you remove a plate w/ 3 or 4 bolts, that includes a kind of cloth that I think will filter incoming air while the motor is in off position.

cjc56 · 10-15-2014, 08:38 AM

If they are suppose to leak vac IN THE OFF POSITION, would not this effect the performance of the engine??

scicala · 10-15-2014, 12:16 PM

Quote:

Originally Posted by cjc56

If they are suppose to leak vac IN THE OFF POSITION, would not this effect the performance of the engine??

I would imagine it is a very slight leak and at idle adjusting the carb idle mixture screws compensates for the extra air from the slight leak. Will not effect open throttle driving. There are a few places that have slight vacuum leaks on the car and cause no harm. (Choke pull-off vacuum piston, throttle shafts and wiper motors etc.)

RCM · 10-17-2014, 04:21 AM

Others will offer a more knowledgable opinion, but I imagine that the vac engine must allow vacuum to equalize with outter atmosfere while you're in the off position. I dont think it would be healthy for the gas pump to be indefinitely sucking air from the "void". Once you slide that channeled rubber into the on position, that incoming air is shut down, and proper depression is created.

cjc56 · 10-17-2014, 05:13 AM

Sponsored Links (Register now to hide all advertisements)

Great observation. That makes sense, thanks.

10-15-2014, 06:43 AM	#1
cjc56 Senior Member Join Date: May 2014 Posts: 123	Do Trico Vacuum Motors leak??? I am looking for a vac leak in my 56 Tbird. The last thing to test was the wiper motor. I found that the motor (when in the off position) does not hold a vacuum. I would think that that means it is leaking when in the off position. Is anyone familiar when these motors and is it normal to leak in the off position. I have 2 of these motors which I have tested and both act the same way. They work great otherwise.

10-15-2014, 08:21 AM	#2
RCM Senior Member Join Date: Nov 2013 Location: Portugal Posts: 374	Re: Do Trico Vacuum Motors leak??? I believe they are suposed to leak. I disassembled mine recently, having never done such thing, and there is a part on its back, after you remove a plate w/ 3 or 4 bolts, that includes a kind of cloth that I think will filter incoming air while the motor is in off position.

10-15-2014, 08:38 AM	#3
cjc56 Senior Member Join Date: May 2014 Posts: 123	Re: Do Trico Vacuum Motors leak??? If they are suppose to leak vac IN THE OFF POSITION, would not this effect the performance of the engine??

10-17-2014, 04:21 AM	#5
RCM Senior Member Join Date: Nov 2013 Location: Portugal Posts: 374	Re: Do Trico Vacuum Motors leak??? Others will offer a more knowledgable opinion, but I imagine that the vac engine must allow vacuum to equalize with outter atmosfere while you're in the off position. I dont think it would be healthy for the gas pump to be indefinitely sucking air from the "void". Once you slide that channeled rubber into the on position, that incoming air is shut down, and proper depression is created.

10-17-2014, 05:13 AM	#6
cjc56 Senior Member Join Date: May 2014 Posts: 123	Re: Do Trico Vacuum Motors leak??? Sponsored Links (Register now to hide all advertisements) Great observation. That makes sense, thanks.