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Sea-Dog
30-11-2004, 11:19 AM
Well in my infinite wisdom I took the top cover off my boost compensator diaphragm to check if it had any pin holes in it and if everything was going ok.. just a general 5 minute health check really!!! I ended up tugging on the diaphragm and the shaft pulled out of the fuel pump... ???

Knowing that the car wasn't going anywhere like that I pulled the top of the fuel pump down and put it all back together again.... now here is the part where you guys come in!

There looks to be 3 areas of adjustment on the fuel pumps that I know of without going too far into changing the settings of the thing... I played with them all!!! ha ha

The boost compensator just under the diaphragm (the cogged wheel) got a few turns etc before I realised that it was not supposed to be turned and I had no idea where it was supposed to be so what I did was to take the thing down a few times at various settings and then start it up and give it a boot full.... initially I smoked the birds out of the nearby trees but eventually I got it to the point where it just gives a small burst of black smoke.. nothing much though!

Secondly was the shaft itself that the diaphragm sits on.. I had that out entirely and just put it back together without realising that it has different profiles in the shaft... I thought it was the same all round and just put it back in whereever!

I also gave the fuel flow screw a tiny half turn out to restrict the fuel flow a little as I had a bit too much smoke out the back when I drove before I played with it....

End result of all that is the car seems to drive a heap better and has more go than before... also doesn't paint the road behind me with smoke when I put the foot to the floor and rev her up to maximum revs. I have a bit more pulling power and can now drive up a local hill in 3rd where I could only do it in second previously. :D

Having played with all these settings and somehow fluked a pass mark with performance, is there any real downfalls or anything that I could have damaged in the process.. I am aware the boost compensator can have an affect on the amount of fuel being delivered at red line revs and can create heat in the motor if driven at max revs for extended periods but in all honesty that won't be happening anyway!

I am hoping that it is a matter of trial and error with these things and I couldn't have done too much harm in the process.... any thoughts! ;)

HDJ105
01-12-2004, 08:39 AM
Sea-dog,

I'm assuming you don't have an EGT gauge?

Without one you really have no idea, other then the smoke output and arse-o-meter as to what you have done and how close to the limit you're running.

But if you backed the main fuel screw out a half turn everything should be safe.

BTW, there's an easier way of getting the compensator shaft back in ;)

DoctorI
01-12-2004, 10:08 AM
Hi SeaDog

I believe it is safe to assume the engine is worth quite a few $$$.
Therefore I recommend getting in to a specialist mechanic who can give it the once over and maybe improve the performance even more or at least make it last a lot longer than leaving it as is and taking a chance that it will last.

Just my 2 cents worth.

Doc

Sea-Dog
01-12-2004, 10:10 AM
After having taken the thing apart on the weekend to put it all back together I would tend to agree that there would be an easier way to put the shaft back in but it would involve taking the shaft out entirely in the first place... it hits on the manifold about one inch up and stops.. I can see how to put it back in if I had it all the way out but not if it is still in but popped up on top of the pin. having said that I have no intention of having to do the job again either in a hurry!

As for the ass-o-meter it seems to be working a bit better and the smoke is definitely reduced.. when I took off at the lights before hand I had a puff of white smoke left behind me for the cars following to drive through... now there is only a very small puff that is barely even noticeable to me..

I would like to have it all done properly but I have a financial shortage that is very restrictive to what I would like to have done to the old girl!

Cheers