Question for my fuel pump M-38

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elias929
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Question for my fuel pump M-38

Post by elias929 »

Hi
I have a fitting brass and oil seems to leak and I want to know if it's missing a hose or I put a plug.

Here this fitting

https://lh6.googleusercontent.com/-p9DI ... 59.jpg[url]

https://lh6.googleusercontent.com/-offa ... 47.jpg[url]

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Last edited by elias929 on Thu Sep 19, 2013 9:21 am, edited 1 time in total.
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wesk
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Post by wesk »

The lower half of your pump is the vacuum booster pump and oil at that fitting indicates the diaphragm has failed and you are sucking oil from the engine crankcase.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

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elias929
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Post by elias929 »

Thus for to settle the problem it must be replaced!

For the fitting it is normal she is not connected on a hose!

Is it dangerous for the engine if I drive a little before change the part!

I appreciate your help!!

Thanks Wes......
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wesk
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Post by wesk »

Thus for to settle the problem it must be replaced!

Replace or rebuild the pump.

For the fitting it is normal she is not connected on a hose!

There are two fittings at the bottom of pump. One goes to the intake manifold and the other to the vacuum windshield wipers.

Is it dangerous for the engine if I drive a little before change the part!

You could plug it like the one to it's left but I would be concerned if the lower vacuum diaphragm is deteriorated then most likely the upper fuel diaphragm is also deteriorated. If that diaphragm fails then you will start getting fuel in your crankcase oil. I would , at this point, be safe and replace or rebuild the pump and plumb the vacuum lines correctly.
Image
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

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elias929
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Post by elias929 »

I read the link on the site

http://www.willysmjeeps.com/v2/modules. ... pic&t=2657

The best place for buy the repair kit or the rebuilt pump, it is Midwest for the parts!!
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wesk
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Post by wesk »

Midwest is very honest and fair with their business. He does offer rebuilt exchange pumps. If you do not wish to rebuild your pump then buy an exchange from him.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

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elias929
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Post by elias929 »

I call at midwest and he is very friendly. it is only the upper kit of disponibility or the rebuilt fuel pump. The pump is not expensive but i think rebuilt my fuel pump with the kit at (Then and Now Automotive)

http://www.maritimedragracing.com/antiq ... cellar.htm

I like to know and understand how does it work......

Thanks Wes!

You are the reference.... :wink:
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elias929
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Post by elias929 »

Is it normal the fitting with rubber hose to metal are going at the transmissioN

https://lh4.googleusercontent.com/-llks ... 065836.jpg
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wesk
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Post by wesk »

That port is plugged in my photo. It is for the fording system and carries crankcase pressures when fording valves are closed to the bell housing and transmission to keep water out. On M38's with the fording system basic plumbing installed it is a solid steel tube from that port to the bell housing. Later M38s have that port vented with the same type vent fitting used in the differentials.

Image

Image
This is the later units without the fording vent system installed.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
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G740
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Pump and oil

Post by G740 »

Hi guys,
The oil in the bottom of the pump does not mean the diaphragm is bad. There is one seal that keeps the oil in the upper part of the pump. It seals around the vacuum diaphragm pull stem. This seal is the problem. I would love to see a Then and Now kit. These pump parts have not been made in a long time and I wonder how they are offering a comprehensive kit and what is included. Anyone have a picture of their kit?
John
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elias929
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Post by elias929 »

I must take the number of the pump before ordering. when i receive this kit i take the picture for you.
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Post by RICKG »

Image
Be advised there are 2 different diaphragm & pull rod types.
Research it and communicate with your supplier (I highly recommend
then and now) before ordering the kit.
keep 'em rollin'
RICKG MC 51986 DOD 01-52, '50 CJ3a
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elias929
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Post by elias929 »

Thanks!!!!

I did not remove my pump but i have the number. (4069) I will order next week....
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