philb Posted April 18, 2010 Share Posted April 18, 2010 Here's the short story: I've just re-built my 7.7 Matador engine, including having the injection pump overhauled (that may be the clue to the trouble but I'm trying not to jump to conclusions). The good news is it now has oil pressure when hot, it doesn't rumble and doesn't leak (quite as much as it did). It starts easily from cold and doesn't seem to be down on power. there's a fair bit of grey smoke when it's cold and off load but it clears quickly once it is on load. At full tilt there's a nice even stream of very faint black smoke, no sign of blue smoke at all. Idling is slow and even, with a little hunting, cold and hot. When it's cold it all works well. The problem is that once it is good and hot coming off load, like when changing up a gear, it takes ages (several seconds but it feels like ages - and much longer than it used to) for the engine to slow down. It doesn't over-speed when dipping the clutch - it just hangs on at the speed it was going at. After revving it up off load it shuts down nice and quickly. I guess the obvious thing is that the control rod is sticking but why from on load and not from off load? I've double checked the valve timing and clearances and also the injection timing by spill test in-situ - all OK. Any similar experiences? Any good ideas to force or isolate the fault (ideally without pulling the pump apart again)? Quote Link to comment Share on other sites More sharing options...
croc Posted April 19, 2010 Share Posted April 19, 2010 Hi Phil, I had a chat with Mike Gilbert and he says it sounds just like his mat runs. Best bet is to let it settle in and not start taking things to bits again. Give him a call if you want to chat about it. P.S. He also says that the very faint black smoke at full tilt wasn't that faint when he was following you. Quote Link to comment Share on other sites More sharing options...
philb Posted April 21, 2010 Author Share Posted April 21, 2010 Thanks Steve. Of the hundred or so folks that have viewed the thread, you are the only one to get the custard cream! I can only see the exhaust in the driving mirror and I didn't think it was smoking much. I'll try pulling back the maximum fuel stop a bit on the secondary adjuster to see if that affects things. My only real concern was that at some time the engine would over-speed and injure itself - without me being able to stall it. Mike did tell me that his sounded much like mine but he didn't mention the running-on issue, I'll talk to him. Meanwhile, just for fun, I'm making a sensor that fits on the back of the idling damper to measure the control rod position and show it on a meter on the dash. How's that for 2010 meets 1945? Quote Link to comment Share on other sites More sharing options...
antarmike Posted April 21, 2010 Share Posted April 21, 2010 Is the spring loaded idling stop correctly set? Quote Link to comment Share on other sites More sharing options...
philb Posted April 21, 2010 Author Share Posted April 21, 2010 Mike, yes I think so. I tried slackening it right back to make sure it wasn't holding the control rod open and that didn't make any difference. Quote Link to comment Share on other sites More sharing options...
philb Posted April 21, 2010 Author Share Posted April 21, 2010 Oops, I just answered the wrong question. I was talking about the spring loaded damper. I think the idling stop is also set right. Idling speed is OK and the accelerator linkage is set so that the spring is just starting to be compressed at that point. There's plenty of travel left to let the engine be stopped by raising the pedal. Quote Link to comment Share on other sites More sharing options...
philb Posted May 16, 2010 Author Share Posted May 16, 2010 Steve, Mike had a drive of my Matador today and it was a "Ah, now I see what you mean" moment. The running on was so bad compared with this that he only wanted to drive it for half a mile and then got me to take over. I'm going to try swapping the injection pump with his spare to see what difference that makes. Quote Link to comment Share on other sites More sharing options...
berna2vm Posted May 17, 2010 Share Posted May 17, 2010 Steve, Mike had a drive of my Matador today and it was a "Ah, now I see what you mean" moment. The running on was so bad compared with this that he only wanted to drive it for half a mile and then got me to take over. I'm going to try swapping the injection pump with his spare to see what difference that makes. Sounds like a good idea to me, this has to be the problem. Quote Link to comment Share on other sites More sharing options...
Tracks & wheels in dir Posted May 17, 2010 Share Posted May 17, 2010 Hello, was the govenor and wheigts in the injector pump worn when you had the pump overhauled?...As this is not uncommon with Matadors in fact a friend of mine uses one for timber exrtaction,and it sits there ticking over fine then for no reason revs itself up which if left would be terminal...Who overhauled your pump and what make is it CAV or Simmons?...There is a good diesel pump man called Peter Strong near Reading Berks Quote Link to comment Share on other sites More sharing options...
philb Posted May 18, 2010 Author Share Posted May 18, 2010 Thanks for your responses. The pump is CAV and the chap who overhauled it said that the governor was fine - I asked him that specifically because it used to "clack" when idling, funnily it doesn't seem to do that as much now. I'm stil trying to find enough spare time to make the rack position monitor, that should show what's going on. I've heard of Peter Strong and, as he's not too far away, I might take it to him after the show season. Until then I'll live with it. Quote Link to comment Share on other sites More sharing options...
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