primary filter help needed.

[jwaller]

ok, so way back when I got my truck I did all the filters and I remember thinking after I did the primary that something just didn't seem right but it ran good so I didn't worry about it.

now I am and I pulled it and am thinking I am missing some parts inside.

what I've got is the canister, 2 washers, 1 seal and 1 umbrella washer/seal.

now I've looked at the TM's and the best pic I found of it was in the -34P and it looks like all my parts go under the filter and thats where I had them. I had nothing on the top of it. and this doesn't seem right.

so what am I missing? and do you have one you can sell me?

 

[OPCOM]

I think the space under the filter, the bottom of the can, is where any water or large amounts of crud go, so you can drain them out before they fill up the can and go to the engine.

 

[jwaller]

yes you are correct but I need to know if any special washer or fitting is supposed to be on top of the filter. mine only had the filter trying to seal against the housing and my old one didn't look like it worked well that way. the cork was bulged in one area and had been passing unfiltered fuel thru that bulge.

 

[WillWagner]

Yes, All the parts go under the filter. From the bottom up; Large washer, spring, small washer, rubber seal ring, (fits tight against the shaft), tin lookin' cup, small end down, (small end seals at the rubber seal, large end seals against the cork on the filter), then the filter. The top of the filter seals against a lip in the filter head.

 

[OPCOM]

Here is the picture, maybe it can help.

 

[73m819]

where did you find that pic, i looked but did not see it

 

[cranetruck]

Another picture, which shows the fuel flow. Think about it, place washers and gaskets so that the fuel flows only thru the filter element to the center.

 

[cranetruck]

The drawings don't show the openings around the center post clearly. The fuel exits around the center not thru it. This image shows the end of the filter. The post or rod is solid.

 

[WillWagner]

That depends on which filter you have. I got the one pictured above from Antelope Valley. The innards of the filter on my truck do not seal the ends, therefore, no filtering. I got the NAPA filter from the x ref list, and it seals fine.

 

[cranetruck]

This is the NAPA filter, it will also seal by placing the washers as shown above.

 

[jwaller]

This is the NAPA filter, it will also seal by placing the washers as shown above.

yup. this is the one I was using and on the filter end the cork had bulged up like fuel was trying to escape out of there. thanks for the pics bjorn they are better than the ones I found. at least now I think I had it on right I just dont feel like using that filter anymore.

 

[cranetruck]

The Facet filter has a military part number. Got it from Memphis for about $25.00. a bit more expensive that the NAPA one, but it's also cleanable.

 

[OPCOM]

Re: RE: primary filter help needed.

where did you find that pic, i looked but did not see it

TM 9-2320-361-20, OCT 1991, page 3-53, figure 3-28.

I rotated it to get 640 out of the 640x480 rule.

 

[houdel]

All fuel filters are not created equal. The military primary filter has a "hump" which fits up into a corresponding recess in the filter head, I suppose for a better seal, but does not have a gasket, so there is a good possibility of contaminated fuel bypassing the primary filter.

I bought a set of Baldwin primary and secondary fuel filters for my truck based on the recommendation in the filter interchange TA that they were the "best fit". The Baldwin primary filter looked very similar to the NAPA filter, a flat top and bottom with a cork gasket at each end. The only problem is, that like the NAPA filter, the center hole is much larger in diameter that the bolt that holds the cannister to the base, so I had to be very careful in assembling it to get the filter centered and squared up so the gaskets had a good seal to the filter base.

The Baldwin secondary filters were a great match to the original military filters and fit without a problem, except I had to order specific gaskets for the cannister (as mentioned in the TA), as the gaskets which came with the filter would not fit.

The following picture shows the military primary filter on the left, military secondary filter in the center, and the Baldwin secondary filter on the right. I did not include the Baldwin primary filter in the picture as I had already installed it, but it was similar to the Baldwin secondary filter, except for the height which was the same as the military primary filter.

BTW, when I changed my primary filter, the washers, spring etc. were all installed BELOW the cotter pin which holds all those in place, so my primary filter was "free floating" on the cannister bolt and not doing any filtering at all!

 

[cranetruck]

The spring holds the filter against a tapered mating surface, granted it's metal to metal, but if clean should seal just fine. If the filter begins to clog up, then the fuel pressure acting on it it will help seal it further.
The surfaces must be clean to begin with for it all to work, of course.
The filter I have, made by Facet, is re-usable and the metal to metal seal will probably last longer than a cork seal. The bottom of the filter is sealed with the cone shaped washer, also metal to metal.
This is after all a "primary" filter and water separator.

Edit: There are lots of examples of metal to metal seals, flared fittings for example. The difference is the pressure, here we are dealing with 10 psi tops. Still, cleanliness is everything.

 

[doghead]

I "borrowed" this info from another reputable mil vehicle site.(I hope no one minds)

I have read a lot of discussion about the correct primary fuel filter for
the M35A2. Some listers have complained that they bought the incorrect one.
Here is what TM 9-2320-361-34P says is the correct filter.
145389 from Allied Automotive
Here are some alternatives that the US Government uses;
M3962 Marvel Engineering Co.
053301 Facet Enterprises Inc.
053754-01 Facet Enterprises Inc.
1-058 Fleetguard Inc.
4089 Allied Automotive
6664482 Purolator Products Inc.
8729068 US Government
929228 Parker-Hannifin

 

[jwaller]

I "borrowed" this info from another reputable mil vehicle site.(I hope no one minds)

I have read a lot of discussion about the correct primary fuel filter for
the M35A2. Some listers have complained that they bought the incorrect one.
Here is what TM 9-2320-361-34P says is the correct filter.
145389 from Allied Automotive
Here are some alternatives that the US Government uses;
M3962 Marvel Engineering Co.
053301 Facet Enterprises Inc.
053754-01 Facet Enterprises Inc.
1-058 Fleetguard Inc.
4089 Allied Automotive
6664482 Purolator Products Inc.
8729068 US Government
929228 Parker-Hannifin

I wonder if anybody has pics of some of these filters to see if they are more like the original

 

[houdel]

I'd like to see one like the OEM filter with the hump at each end AND a gasket at each end to prevent bypass. The metal to metal seal is not real effective, and as the element starts to plug up fuel is going to take the path of least resistance and bypass the element.

 

[clinto]

Ok, I think I must be missing something in mine...... if the pic "primary fuel filter dwg.jpg" is to scale, then mine is missing some kind of spacer......

I did mine today, used the Baldwin.......... see pics...

I do not think I have this right......... ideas?

 

[acetomatoco]

Cork is the way to go..nothing on top as it seals against the housing which has a mating surface cast in. and the washer aka inverted cup on the bottom edge up and then the flat washer spring doohickey and all is good. A point to consider is that the Facet Filter...metal ends has worked well for 40 years And its job is just to keep the water and big pieces of junk out of the other two filters.