cut-outs after reving above 4500rpm

[iani]

Do you have a fuel pressure gauge? It would be useful to see if the pressure is dropping at higher RPM, that would suggest either too narrow a fuel pipe or, more likely, a tired pump.

[GinettaG15]

as said above: the problem is present with mechanical pump and with electric pump..so it cannot be the pump. the fuel-pipes are the usual ones...nothing too narrow...those pipes could feed a 8L v8 engine

[GinettaG15]

Problem solved!!!!

i was right in my assumption "the problem must be fuel related"...but i was wrong with the Needles.

It was the fuel-pump!!!

how comes? the car was originally a 2000cc model....the pre-previous owner fitted an electric fuel pump (his garage fitted it!!). the pump was from a quality brand "Hüco" (they say "made in germany"....but its also distributed as Hitachi Pump...the pump costs ~80pound). this pump is often used from historic car owners to convert from mechanical pump to electric pump. due to its low-pressure which makes it easy and simple to install without having trouble with the float-valves in the carbs.

the pump was installed around 8y ago and the car showed no troubles at the former owners. at least those owners did not recognize anything negative.
the previous owner converted the car to a standard 2500 engine....drove it even long distances to certain meetings...but never rev-ed it, nor drove high speed.....as the engine was consuming oil, a refurbished and slightly tuned 2500 engine was finally installed. the car was driven just 1000miles before selling it to me. due to the running-in period, he never rev-ed it above 4000rpm.

so it was the first time under my ownership, when i really stressed the car and its enigne...and the problem came up.

as the car came with a spare mechanical fuel pump (leftover from the refurbished engine), i temporary installed that pump and the cut-outs were identical. this was misleading me into the direction of the needles.

last weekend i was tidying up the garage and i found a new electric Facet-Pump (the one with the square design) and a Filter-King pressure regulator with fuel-filter
so i thought: why not give it a try and install those parts instead the Hüco pump. i removed the Hüco-Pump, installed the Facet --> test drive-->all fine!!
next day i installed the Filter-King --> all fine!!!

later i inspected the Hüco Pump and found a marking on the pump-body, called "top"..and how was it fitted from the garage 8y ago and no-one recognized it, even 2 former owners? the pump was fitted upside-down!!!

room for speculation left: was the pump tired? or was it due to the wrong mounting-direction?
fact is: problem solved --it was the pump.

[valencia]

It's good to hear that your car is now lively and performing well, if anyone has done a modification previously maybe not a bad place to start the fault diagnosis. If I have a problem with my engine I tend to start by thinking "what did I change from standard spec?"

[GinettaG15]

a question: if i want to convert my car back to a mechanical pump (and just use the electric one for priming after longer storage) which pump do i need to buy?

i know that there are 2 types of levers, one is more flat, one is more curved.

as said, my engine was previously a MK2 PI engine.
apropos PI: does the PI camshaft even has the lobe for the mechanical pump?

[johnnydog]

It's the one with the operating lever at around 45 °
Early Mk1's had a more horizontal lever.
Here is a pic of the two types...

[Matrix]

Hello,

I am in need of fuel pump, and i would like please to verify that i will purchase the correct one as you say there are two types: the early and the late one.
Engine number is MB86934, my father bought the car in 1968 - the update with the air vents and modified upholstery.
Is it safe to say that this is the late model that also uses the modified pump with the inclined lever ?
(perhaps even the revised model used earlier pumps up to a certain MB number ? who knows?)

I have found a fuel pump (attached photo) with the following info.


Part Manufacturer : 213577
Manufacturer Part Number 213577, 7971216

Am i choosing the right one for my car?

thanks in advance!

[johnnydog]

Yes, that picture is the correct profile of operating lever for a late Mk1 2000 - although some models of Mk1 of this era had the solid metal top with an offset inlet union like in your picture, whereas others had the glass topped AC pump with the inlet / outlet opposite each other parallel to the block. Both types will fit and do the job - I believe it was a 'change over' period around that time. I have a 1967 Mk1 2000 fitted with the glass bowl type from when I bought it with only 12,522 miles on it (!) and there was nothing to suggest it had been changed from new!
The difference in the angle of the lever is clear to see in the picture I posted a couple of replies previously.
There were some changes at MB70001 onwards, but the official parts book I have is a bit ambiguous and doesn't clearly indicate the differences at this chassis no.

[Matrix]

hi John,

My fuel pump is the same as yours, with the glass bowl, the AC Delco one, which is considered the most durable of the pumps that Triumph used. (It worked well for 56 years!)
Problem is that i cannot find a new glass one, they are very rare so i will have to get a later type. My mechanic confused me because he suggested to get the early type. But maybe he is not aware of the differences between the two 'versions' of mk1 - besides he is more experienced in mk2s he was an official mechanic of Triumph dealership here in Greece.
After your verification, i feel safe to order the pump i posted above
and i will wish that i will not have issues. Witor site says that there were reports that this type of pump (if it is the same brand) had increased pressure and overfilled carb bowls. I will have to take a risk i guess.
I also hope that the bubbles in the pump are because of some other cause, first he will search the fuel pipes as he said. I also experience cut outs as the OP at 40mph.
Many thanks for your help!

[johnnydog]

No problem at all - I hope the new pump sorts out the problem!