T-2 fuel pump issues

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SPIKE JONES
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T-2 fuel pump issues

#1 Post by SPIKE JONES » Mon May 13, 2019 1:40 pm

The phenoelic (SP?) flange on my '58 developed a severe crack around the threaded insert, so I put on one that I had bought a couple of years ago. After driving the car for about 600 miles, I noticed that I had an oil leak issue from that area. Also, the pump began to act up. So, I pulled the pump and noticed that the ends of the threaded inserts were proud of the flange, causing the seal to fail and leak. I carefully filed down the inserts until they were even with the surface of the flange, then put it back on the 3rd. piece. Upon measuring the minimum and maximum travel of the actuating rod, I found that I now had measurements of 31 & 36 mm (not 29 & 34mm).To compensate, I put on 4 1/2 mm gaskets and re-installed the pump. BTW, I had torn down the pump and replaced the diaphragm with a fresh one and checked everything else before putting it back on.

Now the pump does not work properly...doesn't put out enough fuel to keep the engine running. It will run if I activate the electric priming pump.

Question: Should I remove gaskets (1?, 2?) and replace the pump & see if it runs?
Any suggestions greatly appreciated.
Spike Jones

Dick Weiss
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Re: T-2 fuel pump issues

#2 Post by Dick Weiss » Mon May 13, 2019 9:51 pm

Spike,

I think I answered this before, but reassembling the pump's diaphragm to the lower body, you must preload it to be flat to the surface before you attach the upper body 1/2 w/the 6-screws; Otherwise, the diaphragm will be depressed via its spring and won't pump equally/correctly. Yes, the pushrod's 29-to-34mm dimension is correct. Be sure to add enough grease to the rockerarm cavity.

Dick

Dick Weiss
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Re: T-2 fuel pump issues

#3 Post by Dick Weiss » Mon May 13, 2019 9:57 pm

BTW, Spike;

You preload the rocker-arm to pull down the diaphragm flat to the surface before the upper body 1/2 gets attached.
Use extra hands, or a rod in a bench vice.

Dick

SPIKE JONES
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Posts: 126
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Location: Texas South Plains

Re: T-2 fuel pump issues

#4 Post by SPIKE JONES » Mon May 13, 2019 10:42 pm

Hi Dick,
I did pre-load the diaphragm to a neutral position before attaching the upper half.
Attached are pics of my highly technical device for doing that procedure.
So, if the activating rod measures 36 and 31 mm. from the body of the flange, how many 1/2 mm. gaskets should I put between the flange & the pump?
Anyone?
Attachments
20190511_153613.jpg
20190511_153613.jpg (3.93 MiB) Viewed 435 times
Spike Jones

Dick Weiss
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Re: T-2 fuel pump issues

#5 Post by Dick Weiss » Tue May 14, 2019 9:25 pm

Spike,

If you have the phenolic/fiber mounting spacer w/its gasket to the 3rd piece, you should be OK w/2-gaskets on the pump mounting face, or split the difference w/3- 0,50mm gaskets vs 4 to get the 29-to-34 dimension. I've never had to exceed 2-gaskets unless the push-rod is worn slightly shorter(?); I once had a short one and it had to be replaced w/a new rod.
Also, not to forget that the rocker arm can be worn on its face or a worn pivot pin thru the arm's hole unless new parts are used.

Dick

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Al Zim
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Re: T-2 fuel pump issues

#6 Post by Al Zim » Wed May 15, 2019 9:24 am

All the pre 1963 fuel pumps that we rebuild we resurface the housing where the phonelic seal is held in place by the small coil spring. This situation seems to be most prevalent in the fuel pumps that have brass seats. I never could establish the years those were present my guess is as the T-6 cars were in production. al zim
 

Dick Weiss
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Re: T-2 fuel pump issues

#7 Post by Dick Weiss » Thu May 16, 2019 11:39 am

Also, the problem of the early fuel pump's face-to-the-3rd-piece gets warped over the years of R & R-ing.
If the face is machined, you'll need more gaskets to get the 29-to-34mm position of the push rod.
I don't machine the face having .015"-to-.025"; I restress the face to remove almost all the warpage and
I made a block to finalize the flatness w/emery cloth. Don't overtighten the hardware--same thing on Solex carb feet!

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