Club 80-90 Forums

OK, so I just did a backstreet renewal of cambelt and tensioner (using the stanley-knife technique), and the pump timing is now just off.

Before the job it started and ran sweet, now is starts OK but idles too slow and lumpy, given a bit of throttle it seems fine. I haven't driven it yet as I'm also working on the exhaust.

Any tips on doing a backstreet adjustment of the pump timing ? Presumably there's some way to slaken it off and move it slightly then judge the effect 'by ear' ?

Injection pump can be easily set by ear. The stanley knife method is not a good way of doing the job, you need to set cam timing and then do your pump timing by ear or with dial gauge. Good idea to check valve clearances at same time as cam timing.

It depends if you want to set it or make it worse?
Thing is with pump timing it's a real finicky job, and you gotta get it accurate, tiny amounts of pump movement make a massive difference to the "lift" of the plunger inside the pump.
The only way to get it right is to do it right.
Same with cam timing, near enough is not good enough, bang on is order of the day, a tiny bit either way can make a big difference to running and if slightly off you run the risc of piston to valve interfearance.

OK, panic over. Having got the new exhaust system fitted today, I've now had the chance the give the motor a proper run, and it seems fine.

However I'm sure it could benefit from a tune-up so I'll give Watson Diesel a ring and see how much they'll charge to set the valve clearances and time it up. They were recommended by Jake Stephens and have been trading for 56 years (!) so they should know their stuff. Wimbledon is a bit closer than Huddersfield too.

syncroandy wrote:Wimbledon is a bit closer than Huddersfield too.

A round trip with overnight stay is probably still cheaper though!