Yellow Bullet Forums banner

1 - 9 of 9 Posts

·
Registered
Joined
·
1,418 Posts
Discussion Starter #1
Having some issues with my vacuum pump plugging up and losing vacuum. This is the same combination for years, moroso 3 vane pump, moroso vacuum baffle in front of valve cover, into a moroso catch can, which also is the overflow for the water. After about 30 runs on a new car this year it started to just plug up with a white milky oil and lose vacuum, it slows down 2.5/3 to the 1/8th when it does this. This combo has over 250 runs on it and zero issues until a few weeks ago.

I've checked/changed the obvious. Looked for a float stuck and dripping over, intake gasket change, changed the oil (the oil looks spotless and is not milky and has never milked oil or even showed any signs up milking until this), changed radiator cap, unhooked the water overflow from catch can, changed filters on the catch can. I am also not losing any water. If I clean the vacuum pump with brake cleaner its fine for 2-3 runs and does it again. Could the vacuum pump be going south and just not keeping up ? Or should I be looking for something else ?
 

·
TEAM CARB
Joined
·
45,417 Posts
Id like to hear how much you are pulling.
What happens during a run.
And how much you lose...
 

·
Registered
Joined
·
1,418 Posts
Discussion Starter #5
I do not have the gauge on it anymore, its been on it several times on my other cars. 5 at idle, 12 going down track. It currently quits sucking completely when it plugs up (in 2-3 runs) I can take the suction side hose off the pump put my hand on it and there is nothing, which is when it slows down.

I am getting a pressure checker today for the water side, going to check hot and cold. I figure a head gasket was out after doing a leak down with good results ?
 

·
Registered
Joined
·
1,418 Posts
Discussion Starter #7
Bill I am leaning that way or a crack in the head somewhere. Pressure tested it yesterday, cold no loss of pressure. Hot it lost 5-6lb of pressure in a hour and would lose 3-4lb when I turned on the water pump ( I assume thats not normal). When pulling the valve cover you can now see a lot milk in the oil now which hasnt been the case until after sunday racing.
 

·
TD 3550
Joined
·
3,038 Posts
Mine will milk up pretty quick and no problems with water loss/leaks. Mine sits in a cool shop and with the humidity lately it has gotten worse. I open the overhead door for a couple of hours and fire it, rest assured i have water condensation and have to pull the VC's off and clean them along with the pump and lines. I know you stated this just started. jmo... I have done all the checks also.
 
1 - 9 of 9 Posts
Top