Water Fording Questions

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Nick_
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Water Fording Questions

Unread post by Nick_ » January 23rd, 2017, 11:58 pm

I have an unusual project- a CJ2A chassis with a 1971 M151A2 drivetrain. From what I can tell, my engine has the fording valve. My goal is to refurbish this Jeep and use it for hard trail riding. I've previously restored a Jeep and know my way around them pretty well. The Mutt's are a new territory and I have a few questions:

1. The wiring has been replaced on the starter and alternator. Batteries are exposed. Will I get shocked going into the water with 24V?
2. How well do the engine fans hold up under water?
3. Tranny won't shift into 1st or 2nd but shifts into the other gears.
4. Gas seems to drain into my crankcase, and is almost siphoning out of the fuel tank when I shut off the engine. Fil Bonica believes this is a faulty fuel pump diaphragm.

Thanks and I appreciate all your information. I can't wait to get this thing headlights deep in the mud. For you WWII history buffs, I'm turning this into an SAS/LDRG combat Jeep. My goal is to stand out from the crowd and make the best out of this contraption.

Full build thread: http://www.thecj2apage.com/forums/the-s ... 38325.html

199th mp
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Re: Water Fording Questions

Unread post by 199th mp » January 24th, 2017, 7:42 am

Nick_ wrote:I have an unusual project- a CJ2A chassis with a 1971 M151A2 drivetrain. From what I can tell, my engine has the fording valve. My goal is to refurbish this Jeep and use it for hard trail riding. I've previously restored a Jeep and know my way around them pretty well. The Mutt's are a new territory and I have a few questions:

1. The wiring has been replaced on the starter and alternator. Batteries are exposed. Will I get shocked going into the water with 24V?
2. How well do the engine fans hold up under water?
3. Tranny won't shift into 1st or 2nd but shifts into the other gears.
4. Gas seems to drain into my crankcase, and is almost siphoning out of the fuel tank when I shut off the engine. Fil Bonica believes this is a faulty fuel pump diaphragm.

Thanks and I appreciate all your information. I can't wait to get this thing headlights deep in the mud. For you WWII history buffs, I'm turning this into an SAS/LDRG combat Jeep. My goal is to stand out from the crowd and make the best out of this contraption.

Full build thread: http://www.thecj2apage.com/forums/the-s ... 38325.html
nick, i will speak only to your 2nd question. before entering the water, you must loosen the fan belts sufficiently to allow the fan to free wheel. there are several steps outlined in the manual that give fording info for M151's, but you don't have that complete set up, so i'm not sure if all the other steps apply. make sure that you re-tighten then fan as quickly as possible after leaving the water.

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rickf
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Re: Water Fording Questions

Unread post by rickf » January 24th, 2017, 10:31 am

Well, There are going to be a few variables involved due to the mix of parts. First off with no low range I would not even consider this a heavy wheeling vehicle but hey, it's your cat, make it scratch. The belts can be left tight but several things need to be considered, Are the fan blades in good condition? Check around all of the rivets for cracks. When you go under water keep the rpms down. NOW, here is where the mix of parts comes in, how far from the radiator is the fan? If it is only a few inches then you will need to loosen the belts OR, find a clutch fan from a later model car that will fit. This would not be a bad idea no matter what if there is room because if you have a thermostatic clutch fan then that frees up horsepower when the engine is not calling for fan cooling of the radiator. NOTE i said "thermostatic" clutch. There is also a centrifugal clutch. The most common is the thermostatic and 95% of the time it has a spring type thermostat on the front of the clutch but will always be finned where a centrifugal is usually smooth. You will not be shocked unless you are touching the hot terminal and ground while wet and even then it is iffy, sometimes you will and sometimes you will not. Fuel pump is bad, replace it but if you are going to running under water be sure to get the military one with the vent tube. If you get the civvie pump then rig a vent tube. Won't shift into first or second, pull the shifter out of it's hole in neutral and make sure all three of the forks are aligned in the hole, if not reach in with a large screwdriver and pry the offending lever into the neutral position and put the shifter back in.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Nick_
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Re: Water Fording Questions

Unread post by Nick_ » January 24th, 2017, 10:16 pm

Thanks for the replies; this is great information. The CJ2A has 5.38's so I have a gearing advantage, and I like to keep obstacles challenging.
rickf wrote:You will not be shocked unless you are touching the hot terminal and ground while wet and even then it is iffy, sometimes you will and sometimes you will not.
I'm relieved to hear that. My fear is the shocking treatment used on fish in ponds. I'm running a similar setup, not a generator but still voltage and current.

You're right. I'll go with a clutch or electric puller fan. Most likely electric because it's simple and takes less power. I accidentally half-submerged my 2A once, and the fan blades broke off. Getting out of the vehicle to loosen belts takes away from the experience.

Does the Airtex 60577 have a vent that needs extended, or why would I add a vent if it doesn't?

Fil Bonica
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Re: Water Fording Questions

Unread post by Fil Bonica » January 24th, 2017, 10:53 pm

There is no vent.

You willmstill have to deal with the carb side vents and of course the snorkel:
The valve only prevents water from entering the oil passages.

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svramselaar
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Re: Water Fording Questions

Unread post by svramselaar » January 25th, 2017, 4:01 am

hi

you have several little problems with fording :D

no waterproof wiring
no waterproof alternator
no water tight clutch and brake master cylinders
not all vent are at the air cleaner
do you know if all gaskets at the bell housing and starter are there + plug
rubber at gear stick OK?
take the differential and gearbox breeders with a hose above the water line

see also TM 9-238


greetings george

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rickf
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Re: Water Fording Questions

Unread post by rickf » January 25th, 2017, 10:14 am

I would not worry about the clutch, I ran an old Bronco ans several Jeeps and went under water with them (at least the transmission was under) on a weekly basis and never had any issues. One time I packed the clutch full of mud and the solution was to get it into some deep clear water and let it run for a bit working the clutch. That cleaned out the mud and I put over 150,000 miles on the clutch. Hard miles at that. Water will not hurt a clutch, it may slip under a heavy load but how heavy of a load can you put on it with a 1800 lb. vehicle and 5.38 gears? The vent on the fuel pump goes to the top of the diaphragm and if water fills that area it will hydro-lock and push into the crankcase and you will get water in the oil. That is why you need to fit the pump with a vent tube and route it to the air cleaner. Make sure the tubing for the distributor is all in place also. If the carburetor throttle shaft is worn you can pull water in there, not usually enough to stall it at above idle RPM but if you drop the RPM then it could stall and the last thing you want to do is stall under water.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Nick_
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Re: Water Fording Questions

Unread post by Nick_ » January 29th, 2017, 11:12 pm

svramselaar wrote:hi
you have several little problems with fording :D
see TM 9-238
Yep, I do have some issues in this department. I'm not sure if the Jeep will ever go 100% underwater, but at least to the headlights (I say this now). The bell housing is waterproof as well as the standard 2A master cylinder I believe. Axle breathers are definitely on the list... I may or may not have ruined my first Jeep axle.
My plan is to make a bracket to raise the alternator as high as possible up to the hood, then make some splash shields. I can't justify $300 for a generator plus all the wiring costs. This is a fun side project and if I end up ruining an alternator, I'll consider other options.
rickf wrote:The vent on the fuel pump goes to the top of the diaphragm and if water fills that area it will hydro-lock and push into the crankcase and you will get water in the oil. That is why you need to fit the pump with a vent tube and route it to the air cleaner. Make sure the tubing for the distributor is all in place also. If the carburetor throttle shaft is worn you can pull water in there, not usually enough to stall it at above idle RPM but if you drop the RPM then it could stall and the last thing you want to do is stall under water.
Great story! I'll drill and tap the vent to run a breather tube.
Do the original spark plug wires tend to have any issues with age? I know my greatest safety hazard is a non-waterproof ignition wire, a plug firing into water is not good for me - or the fish.

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rickf
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Re: Water Fording Questions

Unread post by rickf » January 31st, 2017, 5:27 pm

You, or the fish, would never feel it. It will go directly to the nearest ground which in this case would be the wire covering. The original wires are pretty stout as long as they have not been physically abused.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: Water Fording Questions

Unread post by svramselaar » February 1st, 2017, 4:16 am

hi

Rickf
a car has his own circuit it is to the ground
the 24 volt is to low only below salt water it can be there is change the battery`s will drain a bit (salt water is a conductor )
for a person is til 48 volt DC no problem higher as 48 volt and there are amps it can be deadly ( a ignition is high voltage bud has no amps )
the voltage go not to the ground this is only at your house wiring ground and the lightning

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rickf
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Re: Water Fording Questions

Unread post by rickf » February 1st, 2017, 3:17 pm

George, We are thinking along the same idea but in different languages. Yes, on household AC it goes to Earth (ground) and on a vehicle DC system the voltage has to eventually return to the source, the batteries. (Ground)
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: Water Fording Questions

Unread post by Shotgun » April 3rd, 2017, 9:56 pm

FYI, I don't recall any mention of batteries - military batteries are 2HN and are "waterproof" in the context that the fill plugs vent one way, and are supposed to keep out water.
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1968 M151A1 with M416 Trailer
1960 M422A1 (needs restoration) with M416B1 Trailer

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