Bongo Fury

When idling in DRIVE there is a rattly knocking sound which seems to come from the passenger side of the engine hump. It is much less marked or not at all when in N or P. As soon as the engine revs are increased to move off it goes away. It is the sort of sound I would have associated with a broken exhaust bracket. When I turn the engine off the noise (I think it is the same problem) is much much louder as it sounds like the engine shudders to a halt.

It is then very very quiet

I've had the seat up and spent a good while trying to spot the sound with the engine running in D, hoping that the handbrake will not let me down and I'm left riding down the road driver less with nowhere to sit! Without joy because I now conclude that the noise only becomes noticeable when everything is really hot and I hate mixing maintenance with leisure. I cant find any exhaust, cowels, pipes etc loose on the passenger side of the engine.

The engine definitely vibrates more when idling. Could it be a tired engine mounting that becomes more flexible when hot? How would I tell?

Grateful for any advice.
Vehicle details in my sig.

Make sure the alternator and such like bolts are all tight that's a startvpoint

Hi,
you describe exactly what my Bongo was like until recently. The knock was driving me mad, and I tried everything to find the cause. Like you I thought it was connected to the exhaust, but could not find anything.
So I put my Bongo in to a local dealer to have the cam belt changed, and asked them to have a look for the noise while they had it in. When I got it back - magic the knock had gone! The dealer said it was a pipe that went through a chassis opening that was vibrating, and they had put a rubber grommet in there to stop the noise and t worked. Unfortunately I dont know exactly which location this is in, but I was so happy to have the noise gone.
Perhaps another forum user could suggest which pipe this is?

check the gearbox to exhaust bracket, this comes loose.

then maybe check the oil level in the transfer box, it has its own supply that is separate from the box supply.
http://lushprojects.com/bongopartsmk2/c ... no=.html#6

and

http://lushprojects.com/bongopartsmk2/c ... mgno=.html

and item 19-100a torque convertor here.
http://lushprojects.com/bongopartsmk2/c ... mgno=.html

Thanks. Several things to look for.

Thinking I would have found a loose exhaust bracket but making no assumptions - will check again. Alternator seemed solid but again will check - nice and easy. Oil levels sound rather serious

Another reason why it was hard to determine with the seat up is that the noise of the engine itself almost drowns out any knock sounds. Will report back.

another harder one to spot is the crankshaft pulley failure.

the alternator and water pump are together on the pulley, these are bonded on, the aircon pulley usually remains intact on the outer forward end.
the failure is the hard to spot but is usually (heard) when the water pump/alternator pulley comes loose on the centre shaft and spins at a different rate to the rest of it.

11-371 here.
http://lushprojects.com/bongopartsmk2/c ... mgno=.html

Have you tried turning the steering a little when idling? Power steering chatter is not unheard of in Bongos.

I have fixed it, temporarily. Many thanks to your help.

I explored many of the points identified and whilst poking around I had a good tug on a large metal pipe under the passenger seat that runs near to the chassis, into a rubber hose that comes up into the Turbo (I think that is what it is) so presume it to be the air inlet. The resulting noise was familiar! Down by the chassis, a bit awkward to see, there is a bracket welded to the pipe that screws to the chassis through a rubber bush which was worn. I have done a temporary fix using some rubber grommets whilst I obtain a proper replacement (not sure where from yet!). All the work was done from underneath. Thought I would add some pics, partly because I feel the need to try putting pics up here .... and they might even be helpful.

The offending worn mounting viewed from underneath the passenger footwell with the under engine cowelling dropped down.


The mounting removed for inspection and showing it worn through


The rubber bush I now need to replace


Trying out an ordinary rubber grommet for size


Bodge constructed from various grommets and washers to get as close as possible to the spacing of the original


Fix in place with cowelling back


I gave the exhaust clamp by the gearbox a little tighten as well.
All that was left was a test drive. All symptoms gone including the clatter when turning the engine off.
thank you to everyone for your ideas and thoughts.
... now to check those air con pipes ....

Back again, sorry! Any suggestions for the proper name or description for the worn bush are welcome. It will help trying to find a correct replacement. Thanks.

Really useful post cmm303

Thanks

The rubber bush is listed on the Intercooler (diesel) diagram, part 13-363H

http://lushprojects.com/bongopartsmk2/c ... mgno=.html

I hope I'm right with this

glad you got this sorted, this sounds like what the garage was trying to explain to me about mine. Going to get underneath tommorrow and check it out. Like you, I was convinced it was the exhaust!

pc13cb92 wrote:glad you got this sorted, this sounds like what the garage was trying to explain to me about mine. Going to get underneath tommorrow and check it out. Like you, I was convinced it was the exhaust!

It may be a bit difficult to identify in situ. Nothing that a 10mm (?) socket can't quickly reveal though! I'll post when I have the replacement bush from Ian to confirm that I have actually identified and ordered the right part.

well done to the OP for spotting this one. I had identical symptoms and doing a search for the problem was next on my list. Stuck my head under the van tonight and guess what - same problem Thanks for saving me loads of time It only took five minutes to stick a couple of grommets in the bracket, problem solved, i really hate rattles and noises in my cars...

cmm303 wrote: The rubber bush is listed on the Intercooler (diesel) diagram, part 13-363H
http://lushprojects.com/bongopartsmk2/c ... mgno=.html
I hope I'm right with this

Replacement received from Ian today. It's correct.