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-   Diesel Discussion (http://www.peachparts.com/shopforum/forumdisplay.php?f=15)
-   -   307D Kangaroo (http://www.peachparts.com/shopforum/showthread.php?t=202062)

HymerPaul 10-13-2007 10:45 AM

Checked the oil level, it didn't seem to have much in there but I have now toped it up to the level. This has not made any difference, the engine still pulses in and out on tick over and higher engine revs until it is quite high.

perplexed.

kerry 10-13-2007 11:28 AM

Is the accelerator linkage moving with the pulsation? Does the engine have a throttle in the intake?

Oops, I missed RLeo's earlier post. Looks like we had the same thought.
I'm wondering if the throttle has become disconnected, flopping around at low rpm's causing the wandering, but being held open at high rpm's by the high air flow.

HymerPaul 10-13-2007 01:22 PM

sorry for being a bit thick but diesels do mystify me a bit. At the air intake there is what I presume to be two butterflies. One has a rod connected to it that comes all the way back and joins up with the throttle linkages at the back of the engine. The other just seems to be connected to nothing but does have a tag that engages with the other butterfly in one direction only. When the engine is at idle and is pulsating up and down there is no noticable movement in any of these linkages. There is also a pipe that connects between the air intake and the injector pump which is intact with no leaks. Though a high mileage engine it is in good nick and runs very well other than this problem.

HymerPaul 10-14-2007 04:13 AM

After a quick drive down the road this morning looking like a learner driver it is clear I have not resolved my problem. At least England are through to the final so all is not bad this morning.

kerry 10-14-2007 11:40 AM

If the throttle is operating properly, it seems to me that the only cause of your problem can be variation in fuel delivery. I only see two possibilities for the source of this problem. It is either a problem internal to the fuel injection pump or the fuel is not being delivered consistently to the IP. You may be able to test the consistency of fuel delivery by removing the fuel return line and sticking it into a transparent bottle. Watch the stream of fuel for pulsations.
I don't know if a weak fuel pump would produce your symptoms or not.

HymerPaul 10-15-2007 03:03 PM

Just taken it out for a good long run. As usual it started first time but the engine reved up and down at idle. After driving for 20 minutes it settles down and will idle at a fairly constant speed. Wow this is one annoying fault.

R Leo 10-16-2007 03:47 PM

If this was broken governor spring, the idle variation would not improve over time. Likewise, a poorly adjusted pneumatic governor linkage wouldn't improve the idle over time either.

Since it seems to be coupled to engine temperature, tell us more about the operating temperatures on the engine and how long it takes to get to operating temperature.

kerry 10-16-2007 03:50 PM

I'm wondering if it could be a lift pump problem that resolves as the fuel warms up and becomes easier to pump. I think the return line test might possibly supply some additional data.

R Leo 10-16-2007 07:26 PM

After reading more, now I'm thinking this could be a governor issue...I'll scan the pages from the 616 FSM section on adjusting the pneumatic governor.

This thread contains the link I was referring to earlier, unfortunately the original site is gone:
http://www.peachparts.com/shopforum/showthread.php?t=110577

Here it's translated:
http://www.peachparts.com/shopforum/showthread.php?t=202638

Another

http://www.peachparts.com/shopforum/showthread.php?t=8623

Your problem may be solved by nothing more than lubricating the pivots on the pneumatic governor's intake butterfly.

dabenz 10-17-2007 12:18 AM

If the engine is running fine at road speed then it's probably not the governor - you would see that in a "stumble" when you pressed the accelerator (the air flap opens up and the governor is slow in forcing the injection pump to add fuel).

If the engine is "hunting" at idle then it's probably what we in the US call the tickler. Am unsure of the layout in your vehicle, but in a normal car the tickler shaft goes over the valve cover and then down to the rear side of the injection pump. The whole purpose of the tickler is to prevent hunting at idle. If it's not set right then the tickler will fight the governor for control at low engine speeds.

Unfortunately it's an involved process to set the tickler properly the first time. You set the engine's maximum no-load engine speed first, then the low speed idle, then adjust the tickler to take out the hunt. All this, of course, after making sure the linkages move properly and making sure the governor has the proper vacuum at the proper time. The factory manual has the procedure - available on a CD in the US - where in France?

OK - now look at post number 18. One set of linkages that goes around to the linkages that connect to the linkages at the rear of injection pump - this should be the foot throttle, perhaps also a hand throttle also attached at rear of injection pump. The other set of linkages that don't seem to be attached to anything - perhaps the tickler wasn't connected after a valve adjustment? The injection pump connector of the tickler is on the engine side - just forward of the governor. Looks like a little swing-arm attached to the side of the injection pump. What's it attached to? On a regular car it's attached to a set of rod-and-ball linkages that go straight up and over the valve cover.

HymerPaul 10-18-2007 05:12 PM

Thanks to all for the tips and advice. I think I have checked just about everything and can find nothing out of place or not as it should be. I am going off on a long trip in a couple of weeks so will see how it runs after that. I should get a whole tank full with some injector cleaner [clutching at straws now] through the system.

Still sunny here!

HymerPaul 10-24-2007 04:51 PM

1 Attachment(s)
Well its still running OK but the engine still revs up and down at idle. I will get to the bottom of it one day.

http://www.chatenet.co.uk/images/DSCF0013.JPG

klaus kallas 10-24-2007 05:15 PM

Wow!! What a beautiful machine! Wish they had sold those in the States!

Just a thought on your idle. Have you tried pulling the vacuum line off the shut-off switch at the back of the injection pump? Ignition switch connector could be getting weak and allowing a small amount of vacuum to the pump shut-off while running ... ???? It is a brown colored vacuum line (on cars anyway, probably the same on your truck).

Not terribly likely, but takes 2 seconds to check.

Have fun motoring!

Klaus


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