TR5 and perhaps TR6 Fuel injectors

[Bill Bourne]

Hi all

 

Has anyone spotted a difference between very similar injectors.

I've recently fitted some re-conditioned injectors - a set from Neil Raven Smith to the TR5 that I'm re-building and found after some running of the engine, that 2 had failed and stopped working altogether for some reason. Could not be coaxed back to life. the needles seem to have jammed solid. These were Nos.1 & 2. So I changed these for some KMI reconditioned injectors and these worked, but I found I had a small weep of petrol from the olive connection on top of the injector. Did all the usual checks of undo/re-tighten etc, but they still weeped. The next step was to use some fine grinding paste on the neck and the olive to see if that would work. Yep all good and thought nothing more that that was all that was needed. However No.4 went down 2 days ago. So again changed the injector to a KMI injector. All worked, but yet again I had a small weep. This time on closer inspection I can see that the top neck of the injector from KMI V NRSmith is slightly smaller. Why would that be ? Surely the olive size on the pipework is exactly the same? Got some old pipes out - and yes they are the same as the new ones that you buy. OK - next check the part Nos.

 

I think the original TR5 parts book quotes part No.149512 as does the Moss parts book for TR5' and early TR6's

Then the Moss book quotes "for all but early TR5's and early TR6's" the part Nos are very similar i.e 15791 + R for reconditioned - then 15791 R (L) ? I don't know what the L stands for - possibly large ? - but either way there seems to only one type of pipe/olive size on the pipework anyway.

 

Checking the Nos.of the NRSmith injectors and the KMI ones - both have the same part Nos. - but they are different on the top neck. The KMI ones are slightly smaller and hence the weeping issue. Why should there be a difference when the pipe olives are the same.

 

I might be making a meal out of this, but the end result is that I want to know how resolve the weeping, as I'm expecting some other injectors to go down soon like the others.

 

Anyone had experience of this ?

 

best

Bill

 

[stuart]

Why dont you talk to the suppliers. Neil will probably be able to tell you straight away the differences.

Stuart.

[Guest ntc]

Why dont you talk to the suppliers. Neil will probably be able to tell you straight away the differences.

Stuart.

+1

Bill

As it is a new build did you blow the new fuel lines clear before connecting ?

[Bill Bourne]

Hi Neil

 

Yes did all that - and since posting, I've spoken to KMI - 1st time they have heard of a difference, but whilst on the phone, they checked some stock and yep there is a slight difference between some of the injectors with the same part No. Only a mm or so, but smaller and enough not to allow the olive to sit as well as it does in the larger ones. They suggested I send some for testing and in the meantime, when fitting they suggested as a method of fitting. Apply finger ( firmly) tight before putting into the throttle body, then wiggle the pipe a little to try and centre the olive before finally tightening. I'll try that next time. Alternatively I can only lap the olive into the neck of the injector like I've already done to stop the weeping. It's really strange. I've never come across this before.

 

Best

Bill

Edited November 15, 2017 by Bill Bourne

[Bill Bourne]

Here's some picture of what I mean

 

 

Best Bill

 

One of the pictures has turned and I can't seem to get back ugh.

Edited November 15, 2017 by Bill Bourne