New fuel pump causing my really low mpg/ and richness?

[djshutup]

1967 original stock. 30-pict 1
Within the last year new points, valve adjustment, timing, new plugs/wires etc.
Been tracking mpg for most of the year and steadily averaged mid 20's.
The last 2 fillups I have gotten 16mpg and I've noticed the car is getting harder to start after being warm. So finally got smart and pulled a plug and this is what I saw.

The ONLY two things that have changed since the aweful mpg and starting issues is I had the carb rebuilt by Volkzbitz (awesome work)(my shaft was leaking) and my fuel pump was leaking very little

I bought a new one at a VW classic shop till I could rebuild the original and bought this.

I have no fuel pump psi tester to test the new pump but it sure sounds like the problem and how would one even make it the right PSI there is no adjustment. Seems kinda ridiculous they would sell a pump that pumps out the wrong psi.

Forgot to mention idles fine and runs fine just terrible mpg all of a sudden and finicky to start sometimes when it's warm you can smell gas badly when it struggles to start. And I know it's cause the plugs are black that is why its struggling to start according to my book.
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1967 Volkswagen Bug (stock). 1980 Yamaha XS400 Special II (stock). Ya I like stock classics

[KTPhil]

The float valves in carb rebuild kits have been terrible for years. I made a habit of re-using the old ones. Maybe yours is sticking, and the pump is then allowed to overfill the float bowl, causing gad to be pushed out the bowl vent into the intake.

Or it could be the fuel pump.

[EverettB]

Yes, those pumps out out too much PSI.

Yes, they can flood the carb. after you stop, making it hard to start again.
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[djshutup]

well I went and bought a fuel tester from harbor freight and this is what I got.

bounces around between 4.1 and like 4.3

and the book I have says it's supposed to be 2.8... hooray
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1967 Volkswagen Bug (stock). 1980 Yamaha XS400 Special II (stock). Ya I like stock classics

[c21darrel]

you can add gaskets under the fuel pump to lower psi. 1 or 2 will probably get you where you need to be.

[djshutup]

[EverettB]

[djshutup]

wanted to give an update.
Put on 4 gaskets and the PSI didn't change (might have gone up a small amount actually lol). Thought ok maybe the psi tester was screwy and I put my original pump and sure enough checks in at a perfect 2.8.

So long story short the place I bought the new fuel pump is gonna swap it out for another one and I will leave the old one on and monitor for anymore seeping.
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1967 Volkswagen Bug (stock). 1980 Yamaha XS400 Special II (stock). Ya I like stock classics

[andk5591]

FYI - there are different thickness gaskets, but I would have expected some change. Just curious - did you change the base and pushrod or just the pump?

One other thing - those pumps are notorious for the dowel pin that the pump foot rides on working its way out. Have seen it around 4 times over the last couple years. Had it happen on my 65 with my wife driving it on the worse possible section of road at 5PM on a Friday......

This is going to sound stupid to do but - install the pump. Make sure the pressure is good, then pull it back off.

There are a variety of ways folks have fixed this. JB weld over the ends, peening over the ends of the pin(my preferred method), longer pin with C-clips, retaining strap and theres a few others.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them...

[djshutup]

[andk5591]

OK - you dont know that there are 2 different length pushrods for the fuel pumps. Can pretty much bet that is your issue. Do a search for fuel pump pushrod. See this link - theres probably at least a hundred of them.

http://www.thesamba.com/vw/forum/viewtopic.php?t=560704&highlight=fuel+pushrod+length
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them...

[djshutup]

[djshutup]

[quote="vwkind"]

[andk5591]

[Harleyelf]

The other method of achieving this is to grind or lathe-cut the pushrod.

[djshutup]

wanted to give an update as it might help others in the future.

I've tried 3 different new replacement fuel pumps with various gaskets stacked since and the pressures were all between 4-6. I think what others have said (taking the long rod and grinding it down) is the only thing that will work in my case.

I rebuilt my original brosol pump with
http://www2.cip1.com/ProductDetails.asp?ProductCode=VWC-111-198-555
re-installed and PSI was ~4. So I took the main spring out (one attached to big diaphragm) and put the original back on the PSI is perfect at 2.8. Car runs great however overnight I get gas seeping out of

Doesn't leak when it's running or shortly after. Just overnight in the morning its a little wet.
Anyone experience this? It's a lot better then it was before it was leaking out of every screw on the pump before. And yes I preloaded the diaphragm with a jig before screwing down and all the screws are tight tight. Almost like there is too much pressure when the gas evaporates and has no where to go or something I dunno.
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1967 Volkswagen Bug (stock). 1980 Yamaha XS400 Special II (stock). Ya I like stock classics

[estilholliday]

Definately looks like a washer or something is in between that top plate and the body of the pump, causing a gap. You have the screws tightened down on each side which is causing a bend in that plate. Even when you fix that issue, the plate may be warped too much to still be used.

[klroger]

I don't understand the gaskets to shim the pump away from the engine to lower the fuel pressure. If you in effect make the pushrod shorter by moving the pump from the engine block, are you not also reducing the pump volume output as now the pushrod doesn't make the pump travel a full operating stroke??? This whole thing about gaskets reducing pressure doesn't make sense to me... I've always understood the spring makes the pressure. Your pump doesn't always pump, only when it's needed & the spring is what makes the pressure on the needle valve...
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I Didn't know what to do, So I Didn't do anything!!!!

[andk5591]

Yes - by adding gaskets, you are reducing pump volume. It can help with pressure some and I have played around with it myself quite a bit in the past. Also, have done things like shorten the pushrod. Lots of folks do it and seem to get some help in fine tweaking, but the spring is the big thing and anymore I use a correct pump (have had good luck withe new Brosals) or use a pressure regulator. I have stopped using the round dial type and gone to the Holley one.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them...

[kreemoweet]