[DeTomaso] DICK RUZZIN / Mangusta Idle

[JDeRyke at aol.com]

In a message dated 11/6/09 4:58:03 PM, dickruzzindesign at aol.com writes:

> Is there some kind of check valve in the power brake system?
> 
The hose hookup to a vacuum line on your power brake unit is normally a 
check valve. But if the big rubber diaphragm inside the power booster is 
perforated, a vacuum leak may occur. Perforations sometimes occur from the unit 
sucking oil along with vacuum and engine oil rots the diaphragm or the vacuum 
hose; this happens on engines with lots of blow-by, or those with 
non-standard power brake hook-ups. Disconnect the power brake line at the engine and 
plug the hole. If the idle improves, somewhere in the power brake booster, 
lines or check-valve is a leak. I've seen cracked plastic check-valve 
fittings, ancient hoses with holes or cracks and torn booster diaphragms. Good luck- 
J Deryke