Vacuum wipers

[Sundawg3]

Guys,

Another question on the Mutt. I have the vacuum pump which has a lot of oil around it and the surrounding area. I assumed it’s the pump since the wipers don’t work. I found the dipstick loose in the tube and could not find the stopper only so I ordered a new dipstick. It fits much tighter so I believe that’s the issue with the oil blow by. I found vacuum pump kits but how can I test it before buying and rebuilding the pump? Remove a rubber hose at the instrument panel and feel for suction? Do the wipers work at idle or does the RPM need to be high for the pump to run the wipers? Not that I’ll ever drive this thing in the rain ( I did buy new wiper blades) but that’s cause I want thing right. Oil leaks drive me nuts but should I expect that from a Mutt? The radial engine aircraft I’m used to always leak and I’ve always been told you don’t want to fly one that’s not leaking. It’s normal.

[Hambone]

Speaking of oil, if it's not marking its territory, it's not a mutt, pull hose at pump first, see if you have vacuum, if so, trace hose toward wiper motors, checking for air leak, pinched hose, mud dobbers, etc. Wipers should work fine at idle, use a little rainX on the windshield, your wiper motors will thank you.

[rickf]

There are two U shaped metal tubes under the edge of the dash for the wipers. One is the vacuum from the pump to the wipers and the other is the return from the wipers to the air cleaner. These two tubes get water in them and the rust shut. If you have vacuum at the pump but not inside then check here. An old broken speedo cable in a drill works well for cleaning the tubes out. I don't use the return since it restricts the line too much. I leave the hose loosely on the tube for looks but if I need the wipers I pull it off.

As far a the blow by goes it sounds to me like you have a fording valve and it is set in the closed position. This will blow oil past every seal in the engine! If the fording valve is in the proper position or you do not have one then check the PCV valve. I have never seen one of these engines with excessive blow by.

[Horst]

no fording valve on this jeep...

[rickf]

In that case I would take the oil fill cap off and start it up just to verify you do in fact have that much blow by. At idle with the oil cap off you should see nothing coming out in the way of vapor. If you da take the PCV valve out and see if it is clogged, if it is clean it out and reinstall and check again. If you still have a lot of blow by it is time to get your hands on a leak down tester and find out where the combustion gases are getting by. Could be as simple as stuck rings or as bad as a cracked piston or head.

[Sundawg3]

Hey guys,

Thanks for the help. An email to the Mutt Guru helped as well. Turns out the vacuum lines were bad behind the panel, new rubber and correctly connected the wipers showed some improvement. The metal lines under the panel were blocked just as I was told. Someone made a gasket for the drivers side wiper motor but wasn't making the seal. New paper gasket fixed that issue. With the new gasket on the drivers side the passenger side works like it should. Drivers side was slow but showed promise. A little too much muscle on the wiper arm proved to be the wrong idea. Guess I'll order a new one now. Upon further inspection the manual wiper arm was in contact with the windshield defrost metal deflector. The passenger side has a cutout but drivers doesn't, until I gave it an attitude adjustment with a ball peen hammer!! Works perfect!! Thank you all.