something splattered on left front fender after driving

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something splattered on left front fender after driving

Unread post by Cav Trooper » August 5th, 2018, 10:05 am

I'm getting something splattered on the left front fender after driving. It is an oily substance and I see what is probably brake fluid residue seeping around the master cylinder rubber boot. I have a fording kit installed but the master cylinder cap is not plumbed in. Is is possible that I'm getting brake fluid blown out of the master cylinder vent and onto the fender? Also, where do I find a fording master cylinder cap and a picture of the connecting lines as installed? The spots are just oily looking small spots and wipe off with naptha.
Thanks
CT

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Re: something splattered on left front fender after driving

Unread post by m3a1 » August 5th, 2018, 10:14 am

Tought to say anything because you don't say if it's the inside of the fender or the outside (or which fender for that matter).

In my experience, spills from the cap of the mastery cylinder inevitably result in brake fluid on the floorboards.

Let's rule out a wheel cylinder first just to make sure you don't die during the process of elimination. Check the insides of those wheels and tires to ensure they aren't "wet".

What does that substance smell like?

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Re: something splattered on left front fender after driving

Unread post by Fil Bonica » August 5th, 2018, 10:33 am

Look for weeping around the valve cover gasket.
That and the wind could cause spotting.
The masrlter cylinder would have to be overfilled to the brim to drip and as said typically drops to the floor.
Dont ask me how I know!!!
The m/c cap isnt really required to have the vent connection.
It’s really for fording.
If you are a purist and dont have it you could drill and tap the one you have.

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Re: something splattered on left front fender after driving

Unread post by halftracknut » August 5th, 2018, 6:46 pm

Water pump?
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Re: something splattered on left front fender after driving

Unread post by Cav Trooper » August 6th, 2018, 12:15 am

Left front fender flat on outside near the master cylinder is where the splatter spots are, small ones, maybe a dozen, which spread out on the flat paint. No splatter marks as far forward as the fording cutout on the hood. Some weeping around master cylinder body seal, m/c plug was very tight, copper gasket in place. Silicon brake fluid. Found brake fluid leak/drip on bottom of master cylinder inside on floor. Snugged up the brake line with a fitting wrench, really wasn't loose but got a slight turn on it. Brakes are nice and firm and responsive, no pumping needed to stop, good pedal. Plug in bottom of m/c tight. M/c not over filled, fluid about 1" down from plug threads. I have a fording kit installed but don't have the m/c cap for fording, just the pin hole breather type. Maybe I should plumb the line into the cap if that's where the fluid is spitting from. I've cleaned off the area a couple of times with VMP Naptha and it stays clean until I drive it a distance and it shows up again, nothing inside hood, only a couple of drops on the side of the hood near the m/c, most is on the flat of the left front fender in front of the m/c cap. I removed the m/c body seal and wiped it off just to make sure it's not just residue from over fill or spill.
Whole other story about oil inside left front fender in engine compartment and firewall left side, light film of oil covering there, just enough to see that there is oil film on the paint and alternator and a drip on the underside of the carb.
New radiator cap and oil filler cap on valve cover.
Water pump seems to be ok, no antifreeze leaks, nothing dripping. valve cover is tight, no oil leaks, don't seem to be any leaks from front crankshaft seal. Oil pan is a little wet and after driving it 50 miles at 50 mph part way, I got an oil spot about 2" dia. that dripped off the front differential when I parked it in the garage. nothing leaking from the diff. seals, all dry.
I hate leaks and just trying to seal up as much as possible. Paint is the 383 carc substitute so it shows oil spots really bad. Right side of the engine, right inside fender and firewall all dry, no oil residue at all.

I'm going to try to snug up the pan bolts to see if they are part of the issue. Sure looks like a PIA to replace a pan gasket.
Am I crazy to think the engine compartment can stay fairly clean or at least no oil film?

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Re: something splattered on left front fender after driving

Unread post by rickf » August 6th, 2018, 8:50 am

I hate to say it but this is a 60 year old engine design, you are not going to be able to keep it pristine clean and free of all oil residue and still drive it. Cork gaskets by nature weep oil, that is what they do. That is how they stay supple and do there job so if nothing else you will have oil residue there. And the differentials and transmission seals are a nightmare in there own right. How many vehicles do you know of that have 11 seals? And that is not counting the transmission input seal. The odds of them all staying dry at the same time are slim considering even NOS seals are 30 years old when you buy them. And on that note, how many vehicles do you know that have 12 u-joints that need constant attention and the associated slinging grease?
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: something splattered on left front fender after driving

Unread post by Cav Trooper » August 6th, 2018, 10:24 am

Ahh, I get it, live with it and be happy to own one. I'll keep a rag and a can of gunk around. Thanks Rick. BTW, thanks for the carb adjust information, I haven't tried it yet, may just leave well enough alone.
CT

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Re: something splattered on left front fender after driving

Unread post by m3a1 » August 6th, 2018, 10:38 am

Man, if you're trying to solve problems on your fender top by working on the oil pan, I've got a few jobs around here for you to do! :lol:

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Re: something splattered on left front fender after driving

Unread post by halftracknut » August 6th, 2018, 7:16 pm

Not Jeep related but.....B25 Mitchell take off check list....use 9 rags to clean up oil splatter and leaks means it is a go!.....................use 10 rags you are grounded.......... :wink: :mrgreen:
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Re: something splattered on left front fender after driving

Unread post by Cav Trooper » August 6th, 2018, 9:49 pm

Two different issues, one is the splatters that appear just in front of the master cylinder plug after driving a few miles and appear to be brake fluid (silicon). The other is the oil leak some place low on the left side of the engine that covers the inner left fender, alternator and left side firewall with an oil film. I'm not that stupid to think they are the same problem.....I'm not 20, I'm 70+ and worked on a lot of vehicles, just not familiar yet with the M151 and when found long ago, asked those who know before barging in what may be a fruitless cause. When I bought this vehicle it was suppose to be leak free and upper half is. I've chased leaks on an '86 12 cylinder Jaguar and fixed them where the Jag mechanics couldn't, I assumed I could find and fix a 4 cylinder American built engine oil leak. I found the one around the fuel pump early on and fixed it, right side is now bone dry. Thanks for your input and if asking an honest question on this board gets a condescending response, I'll go elsewhere. I understood what rickf and Fil were explaining and respect their opinions and thank them for the information.

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Re: something splattered on left front fender after driving

Unread post by rickf » August 6th, 2018, 10:50 pm

All joking aside, if you managed to get the right side of the motor sealed then you accomplished the hardest part short of the valve cover. There really is nothing to leak on the left side, other than the valve cover but that is up high. The only other thing with oil in it is the air cleaner. I have seen them rot holes in the bottom when they were never serviced and they had water laying in the bottom. Another possibility is antifreeze blowing back from the overflow tube that runs down the side of the radiator.
12 cylinder Jags sucked! They ran so damn hot they required straight 50 weight oil and you had to wear a glove to check the dipstick. I hated working on those cars.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
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Re: something splattered on left front fender after driving

Unread post by Mark » August 7th, 2018, 8:41 am

Could a bad PCV be causing the leaks?
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Re: something splattered on left front fender after driving

Unread post by rickf » August 7th, 2018, 9:20 am

If you bad as in clogged then the first place the engine usually leaks is the rear main seal. That is actually how a fording valve works is by shutting off the PCV system and letting the blowby pressurize the engine. That is why there is a data tag that tells you to open the valve as soon as you are clear of the water.
The crankcase breather goes up to the brass fitting on top of the carb so even if the crankcase pressurizes and excess vapor comes out it will go directly into the carburetor. Oil would come out the front and rear seals first and then the valve cover and side covers if you were really hammering on it. There is nothing on the side of the engine on the drivers side that would leak oil, other than a valve cover leak and that would have to get by the exhaust manifold first so you would see smoke also.
1964 M151A1
1984 M1008
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AN/TSQ-114A Trailblazer- Gone

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Re: something splattered on left front fender after driving

Unread post by raymond » August 7th, 2018, 10:17 am

Freezeplug :?:
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Re: something splattered on left front fender after driving

Unread post by Cav Trooper » August 7th, 2018, 7:46 pm

Thanks Rick, no smoke, valve cover gasket and top rubber bushings tight. I can run a rag around and pick up nothing from the valve cover seal area, nothing running down either. Nothing on the back side of the pulleys and it would have slung oil to the inner fenders on both sides which it has not. It's only driver's side from around mid alternator back to firewall and nothing into the tunnel. It's not heavy either, just a film, nothing dripping other than the puddle after a long high speed drive on a hot day. Could not see where it came from with a trouble light and crawling under it. I have a friend with a lift and I may see if I can run it over and put it up on the lift to see anything. Engine and engine compartment were pristine clean, fresh paint on both when I got it. Probably only had 25 miles on it. You know the work Vin does, outstanding. No antifreeze leaks, a little blow off from the overflow but I could tell the difference between antifreeze and oil and there was an oil drip on the bottom of the carb. All hoses are tight and new. I'll check the air cleaner bottom, I checked all around the upper to lower sections and dry as a bone. I may add a short hose to the overflow tube just for S and G's, trying to sort out or give up. With it looking new, I just want to keep it close to that as long as possible. Thanks all. I'll leave the subject at this point. No sense beating a dead horse. I may see if I can plumb the brake cap into the fording fitting. I'll have to find a cap or drill and tap the one I have and find the correct fittings.

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