Don't call it a knock

Czakky · Posted: Thu Oct 16, 2014 10:32 am Post subject: Don't call it a knock

Since I have had my 71 super w/generator(about a month) it has always had this somewhat quiet.... Er, rattle. Goes away after about 1500 rpm sounds the same cold or warm, i have very miniscule play at the crank pulley and I can feel the "rattle" on top of the new -looking pump.

Please tell me this is fuel pump pushrod issue I couldnt find any similar issues on the forum.

mtdorajohn · Samba Member Joined: June 02, 2010 Posts: 674

your fuel push rod is driven off of the distributor gear. no way of knowing if you are correct in your diagnosis, but you can pull it apart and see....

the push rod could be short, aka, worn down, or a miss match for the fuel pump... your distributor drive gear could be worn down at the bottom where it sits on the case too.... all of this can be reviewed with the engine in place though....

.... welcome to the VW club though; .... as we always say in this forum.... NO PICTURES?... we can diagnose anything without pictures....

...I think we say this just because we want to make sure your bug isn't better than our bug... and pictures are the easy way to say... "glad I don't own that bug..."

mtdorajohn · Samba Member Joined: June 02, 2010 Posts: 674

oh, just saw your location... don't miss bug jam in Dade City this weekend...

Cusser · Posted: Thu Oct 16, 2014 11:48 am Post subject:

I think if you wanted to determine whether this was a fuel pump pushrod issue, you could pull the FP, remove the rod, bolt the FP back on, and run for long enough to tell if noise was gone just using the fuel already inside the carburetor bowl.
_________________
1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297

Czakky · Posted: Thu Oct 16, 2014 2:12 pm Post subject:

Her74buggy · Posted: Thu Oct 16, 2014 3:04 pm Post subject:

No, you buy the rod separately, just make sure it's the right length. I imagine if yours is running okay. As in getting fuel, you have the right size rod. It could be worn down a little but if you are getting fuel I bet there's no slack. If you are removing the pump make sure there is grease packed in the pump base. You said it's new so maybe it's noisy due to lack of grease on the lever?
Pictures help.....

fla2smoker · Posted: Thu Oct 16, 2014 3:44 pm Post subject:

mtdorajohn · Samba Member Joined: June 02, 2010 Posts: 674

I had it on my calendar wrong... thanks for the info... id be lonely if I'd have driven down this weekend..

HRVW · Posted: Thu Oct 16, 2014 9:59 pm Post subject:

:roll:Lot of headaches for some people that are not needed with the newer style of fuel pumps.

There are only TWO fuel pump rods for the 1200 and up engines.

Early Gen had the longer rod and when the Alt came out VW used a shorter rod.

Headache come with the different fuel pumps on the MKT that are for the Alt style while they used the longer rod instead of the VW short rod thus broken pumps.

If the flange hangs down out of the pump then the longer rod was used and if the flange was inside almost flush with the pump then the short rod was used......at least that is what I found on the MKT yrs ago.

Cannot vouch for what is available today as I've been out of the trade for a while (retired)

Something to consider.

johnnypan · Posted: Fri Oct 17, 2014 6:45 am Post subject:

Make sure the spring between your distributor and distributor drive shaft is there,and isn't crushed..it keeps the drive from jumping up and down..the distributor drive shaft also drives your fuel pump pushrod.

Czakky · Posted: Fri Oct 17, 2014 11:18 am Post subject:

Not sure if this helps
https://m.youtube.com/watch?v=j8jpTT9B-ZU

johnnypan · Posted: Fri Oct 17, 2014 11:48 am Post subject:

tighten your belt and adjust your valves..

Czakky · Posted: Fri Oct 17, 2014 12:44 pm Post subject:

I think my belt is really old waiting on a new stock pulley/ belt. I'm pretty confident in my valves adjustment torqued heads all that 500 miles ago. Sound doesnt seem to come from Valves but I could be wrong....

Czakky · Posted: Mon Oct 20, 2014 8:03 am Post subject:

So i went ahead and greased the fuel pump and measured the distance on the fuel pump push rod and at the highest it is 11.5 mm the lowest it is 7.5 mm above the plastic flange...
This is waaay too much fuel right?

Czakky · Posted: Tue Oct 21, 2014 3:59 am Post subject:

Anybody have any input?

Her74buggy · Posted: Tue Oct 21, 2014 8:21 am Post subject:

Check my post
http://www.thesamba.com/vw/forum/viewtopic.php?t=609631
The key is to assure the pump and rod length match. No pics makes it hard to give advice. If you have a pump that need a short 100mm rod or a longer 108 mm rod then that match has to be there. If you've changed nothing and your pump works I imagine you have the right size rod but is it worn down? You have to pull it out and measure. Easy if the pumps off, just lift it out. If it's worn they are about $3.

Czakky · Posted: Wed Oct 22, 2014 11:21 am Post subject:

Pretty much eliminated the pushrod as being the "noise maker" for now. The startling thing is that my pulley does seem to have some play in it when it is in the right position. Oh boy!

I will adjust my valves again this weekend just to absolutely eliminate that as an issue.


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