Which fuel pump should I be using???? LATEST NEWS!!!!

[Fraggle]

Hi

I have a 1600cc twinport on an AD code. It's a vw mexico engine.

Which fuel pump should I be using and how long should the pushrod be?

I have one fitted but this came with my old engine which had a alternator and my new engine has a dynamo.

It works but I am experiencing a hesitation / stumble at mid range RPM. Could I have the wrong pump or pushrod length? The engine seems a bit underpowered also.

Could this be it or actually nothing to do with the fuel pump?

Any help much appreciated

 

[slammedresto]

sounds more like a carb problem ive had recently

blocked jet in the carb = fuel starvation

 

[Tofufi]

I'd say it doesn't sound like the fuel pump. But strange things can occur with fuel pumps etc

Have you checked the timing and carb?

Which distributor do you have?

 

[Fraggle]

Cheers guys.

I've got brand new everything except from coil and fuel pump as they came off old engine but looked ok.

I have twin Weber ICT's again brand new.

Piss me off!!! :evil: :evil:

It only happens under load and at mid range revs but overall there is a slight lack of power I recon. I've had a few 1600's now so know what they should feel like.

Give me strength!!!!

 

[Fraggle]

I'd say it doesn't sound like the fuel pump. But strange things can occur with fuel pumps etc

Have you checked the timing and carb?

Which distributor do you have?

A 009 cheap copy that came with the new mexico engine....hmmmm!

 

[james_stan]

Hi

An alternator pump will fit both alternator and dynamo engines with the correct rod length. A dynamo pump however is too tall for the alternator though I think.. can't remember which has the longest rod but it might be the dynamo version..

Cheers

james

 

[Tofufi]

I'd say it doesn't sound like the fuel pump. But strange things can occur with fuel pumps etc

Have you checked the timing and carb?

Which distributor do you have?

A 009 cheap copy that came with the new mexico engine....hmmmm!

Hmmm

If I were you, I'd replace it with a vacuum advance.

In my experience, it'll give better performance and economy. And no flat spot.

I've heard the cheapest 009s aren't the best quality. A friend and I tried fitting one to his bus only to find that it wouldn't advance evenly and the advance wandered everywhere. There has been some discussion on this over on VZi recently.

£20 for a secondhand original German vacuum/centrifugal dizzy wins any day.
And, I believe the ICTs have a take off on the carb.

Have you driven buses with 009s before?

 

[pete nice]

Have you set teh valve clearances is always my first question.

Then check you have .55 idle jest in your ICT's & not.52's that will make a difference. Make sure they are not blocked too.

Points gap can do that too.

 

[slammedresto]

sounds more like a carb problem ive had recently

blocked jet in the carb = fuel starvation

my problem WAS the carb, but was ALSO a dodgy fuel pump

 

[Fraggle]

Cheers for the replies guys

The situation so far...

I have replaced the fuel pump with the correct dynamo one along with the push rod. I have replaced the coil and plugs with brand new.

and......

it feels worse!!!! :roll: :roll: :roll:

This ain't no flat spot it's something propper wrong. Tomorrow I will be stripping the ICT's and checking jets etc, check valves (again) then trying again!

A friend has some ICT's which he agreed to lend me to try just in case.

If that don't diagnose it then it has to be either the dizzy or the engines simply fooked!!!!!

I'll let you know the result so fingers crossed :wink:

 

[Fraggle]

Out of interest is there a specific way the jets have to be fitted / located in the carbs??

Just a thought as I stripped them for cleaning prior to fitting as I had some swarf in a previous set I owned.

Could I have put the jets back in wrong????

 

[pete nice]

Te jets are fairly straight forward, I don't think you can get them wrong.

Idles should be .55's & mains should be 135 or 140.

 

[Tofufi]

If I were you, I would check the timing side of things first as it is easier to check if you happen to have access to a spare dizzy?
I do wonder if your dizzy clamp is loose. Hope I'm not stating the obvious, but with new things like coil etc it could have been bumped round more.

I'd also suggest you check the points gap too - my bus had a points gap too small and it run like crap until it warmed up. Flat spot city!
Good luck anyway

 

[Fraggle]

BREAKING NEWS!! :lol: :lol: :lol:

Stripped the carbs and found that one has a weird cross metal contamination at the bottom of the main jet stack. There was a small piece of metal approx 2mm by 2mm floating about at the bottom.

I whipped that out and thoroughly cleaned them and reassembled...

Sorted!!

I did however notice that they have .52 idles rather than .55's will changimg them really make a difference Pete??

Also how do you check and set float levels??

Here's a pic of mine

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The pic of the above floats were my righthand carb and when upside down it pushed the ballbearing in with the weight of the float, With the other side there wasn't enough weight tp push the ballbearing in?? Thought it was slightly odd but who knows?

Anyone got a pic of the inside of the carbs detailing which jet does what as not totally sure?