Defective Bosch Pump?

[rvwp]

Hi all, following on about my previous topic re sudden loss of pressure at the MU, I am pretty sure that I've got a dodgey Bosh pump. The pump has only done about an hours running in the garage, and as advised by Moss ( cause we've sold 200 and never had a problem!) I have replaced the low pressure filter that comes with the set up supplied by Moss to no avail. In fact I cut up the old filter to check and it was perfect, (another £20 quid down the drain). The pump was working well with the required 106 psi at the MU until it suddenly the car refused to start and a check of the pressure showed it down to 50 psi. I have checked that fuel is free flowing to the pump. I have even temporarily blocked off the PRV return and still no improvement. The complete Injection system from tank to injectors is brand new.

 

Has anybody known of the Bosch pumps failing so soon? I guess that as the pump is only now probably used for TR injection that they are probably made in the far east and made down to a price for Moss which leaves the question !!

Thanks Rich

[Andy Moltu]

No - they seem to be reliable & I guess you've been unlucky.

[Bill Bourne]

Hi all, following on about my previous topic re sudden loss of pressure at the MU, I am pretty sure that I've got a dodgey Bosh pump. The pump has only done about an hours running in the garage, and as advised by Moss ( cause we've sold 200 and never had a problem!) I have replaced the low pressure filter that comes with the set up supplied by Moss to no avail. In fact I cut up the old filter to check and it was perfect, (another £20 quid down the drain). The pump was working well with the required 106 psi at the MU until it suddenly the car refused to start and a check of the pressure showed it down to 50 psi. I have checked that fuel is free flowing to the pump. I have even temporarily blocked off the PRV return and still no improvement. The complete Injection system from tank to injectors is brand new.

 

Has anybody known of the Bosch pumps failing so soon? I guess that as the pump is only now probably used for TR injection that they are probably made in the far east and made down to a price for Moss which leaves the question !!

Thanks Rich

Hi Rich - Just a thought, but I had this happen to me once. Have you got any sealant on your pipe joints - maybe a bit has got into the pump - a bit unauthordox, but try reversing the polarity for a moment to see if it clears. I did and hey presto out popped a bit of sealant..

Best Bill

[Alec Pringle]

Hi Rich,

 

the Bosch pumps are pretty standard units, widely used in the past. I used to be familiar with Bosch units in other applications, and they certainly were NOT bulletproof, contrary to popular belief amongst TR men. 15 years ago as a motor factor I used to keep a shelf full of Bosch pumps . . .

 

However, premature failure was rare, as opposed to failure after tens of thousands of miles. To their credit, on the rare occasions that I've experienced a problem with Bosch injection equipment the response was no-quibble, and by return. My old colleagues only recently mentioned in conversation that Bosch service is still just as good.

 

So don't give up hope

 

Cheers,

 

Alec

[PILKIE]

Had a similar problem when setting mine up after its layup and repaint! Thought the pump was playing up! It turned out that I didnt have quite enough fuel in the tank,and whilst jacking it up when it was running had sucked some air into the system that was a swine to bleed out. Keep a good 5 galls in the tank when its parked up during its resto! Its quite surprising how much fuel it uses when you start it up on choke,warm it up and play with it for a while without going anywhere

I also found a dodgy leccy connection in the boot that gave an intermittent on off effect with the pump that didnt help matters.

Just shows what gremlins can pop up, either one at a time or a few together to throw any diagnosis way off!

I would disconnect the fuel line from the MU and run the pipe into a fuel can then run the pump for a good while to see if it stops and starts at all,this will also help clear any debris that may be in it! Dont forget the tank level!!

I spent nearly an hour trying to find a fault once,only to discover I was out of fuel! I felt a right pratt!

[rvwp]

Hi guys, just to let you know that my problem was'nt the Pump. In fact it turned out to be the MU!. The MU was purchased from a reputable TR spares factor who advertises in TR Action as selling KMI Metering Units. It turns out that the MU sold to me is'nt a KMI unit but refurbished by an unknown business in the Midlands. The problem was that the pump could'nt maintain pressure at the MU because seals had broken down in the MU allowing free flow of fuel back to the tank via the overflow.

 

On top of that the TR spares factor has refused to accept responsibility because I purchased the MU along with a load of engine bits (£1400 worth) over year ago in advance of when I actually needed them. As it's outside the guarantee period they don't want to know even though the MU has only done 1/2 hours running!!

 

I've now sent the MU to KMI who are going to sort it out at my cost.

 

The moral of this story is make sure when you buy in advance that you check the warranty period and your getting what you think you ordererd.

 

Rich

[Chris_TR6]

Hi,

I fitted a replacement bosch pump to my TR6 early last summer. I noticed a strange noise from the pump right from the start but thought nothing of it as the noise soon went. I have done around 500 miles since. However, yesterday I heard a worrying grinding noise coming from the pump and no less than 5 miles later i was having to call the AA out for a tow home.

 

Chris