Excessive vibration whilst stationary

Technical questions and answers about the Mazda Bongo

Moderators: Doone, westonwarrior

duncsuk

Excessive vibration whilst stationary

Post by duncsuk » Tue May 19, 2009 11:22 pm

Following a recent cambelt change, along with new oil/oil filter/air filter/fuel filter, I'm now aware of uncomfortable vibration whilst in gear - ie. waiting at traffic lights. I can feel the vibration up my back and through the steering wheel. In neutral, it reduces, but is still present.

I have tried increasing the idle speed slightly (I guess its now around 800 rpm in neutral) which has helped matters a bit.

Could changing the cambelt (and the subsequent alignment of the new belt) lead to such vibration ?

It's a 1995 diesel Bongo with 97Km on the clock. The car starts fine and there is no apparent vibration problem when moving. Since the cambelt change, I believe the engine noise to be higher .. but it's hard to compare !

Need to compare vibrations with someone else :wink:
User avatar
mikeonb4c
Supreme Being
Posts: 22877
Joined: Sun Nov 05, 2006 10:49 pm
Location: Living with Mango Bongo in the North West but with a tendency to roam
Contact:

Re: Excessive vibration whilst stationary

Post by mikeonb4c » Tue May 19, 2009 11:28 pm

I remember when I had a new cambelt put on my Spacewagon, I could really feel the vibration from - I guess- the notched belt thrumming on the notched pulley. It diminished a bit as the belt bedded in but was never as quiet as the old belt. I wonder if you've got a bit of the same (could it be brand of belt). Never caused any trouble though. Maybe a Bongo techie can comment on this?
User avatar
haydn callow
Supreme Being
Posts: 5777
Joined: Mon Jan 08, 2007 9:50 pm
Location: Somerset
Contact:

Re: Excessive vibration whilst stationary

Post by haydn callow » Wed May 20, 2009 7:54 am

Perhaps the tickover speed was disturbed doing the belt change....try increasing it a bit.
http://www.coolantalarm.co.uk
Developer of the Mazda Bongo Coolant loss Alarm
Also BMW Clocks
User avatar
mikeonb4c
Supreme Being
Posts: 22877
Joined: Sun Nov 05, 2006 10:49 pm
Location: Living with Mango Bongo in the North West but with a tendency to roam
Contact:

Re: Excessive vibration whilst stationary

Post by mikeonb4c » Wed May 20, 2009 12:57 pm

haydn callow wrote:Perhaps the tickover speed was disturbed doing the belt change....try increasing it a bit.
Think he's tried that hasn't he?
I have tried increasing the idle speed slightly (I guess its now around 800 rpm in neutral) which has helped matters a bit.
rabbitsquasher

Re: Excessive vibration whilst stationary

Post by rabbitsquasher » Wed May 20, 2009 1:36 pm

havent got an engine mounting worn have we?
duncsuk

Re: Excessive vibration whilst stationary

Post by duncsuk » Wed May 20, 2009 2:48 pm

rabbitsquasher wrote:havent got an engine mounting worn have we?
hmmm ... how would I check and is it easy to replace ?
scarlet
Bongonaut
Posts: 31
Joined: Fri May 16, 2008 8:15 pm
Location: middle somerset
Contact:

Re: Excessive vibration whilst stationary

Post by scarlet » Wed May 20, 2009 3:07 pm

could the timing be slightly out? i would ask the garage that changed the timing belt if they could just check the timing again.
no-one puts 'baby' in a corner
User avatar
dreamwarrioruk
Supreme Being
Posts: 2226
Joined: Wed Sep 28, 2005 7:39 pm
Location: york
Contact:

Re: Excessive vibration whilst stationary

Post by dreamwarrioruk » Wed May 20, 2009 3:09 pm

not stating the obvious but are the seat clamps fastened correctly if these were loose the seat would move and you state your feeling vibes in your back or it could be the timings out if you have had to raise the idle speed you woulnt accedently knock that when doing a cambelt
mike, jo and emma
User avatar
dandywarhol
Supreme Being
Posts: 5446
Joined: Mon Dec 19, 2005 10:18 pm
Location: Edinburgh

Re: Excessive vibration whilst stationary

Post by dandywarhol » Wed May 20, 2009 4:47 pm

If the idle speed changed AFTER changing the belt i'd say the timing is a tooth out.
Whale oil beef hooked
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
rabbitsquasher

Re: Excessive vibration whilst stationary

Post by rabbitsquasher » Wed May 20, 2009 7:33 pm

dandywarhol wrote:If the idle speed changed AFTER changing the belt i'd say the timing is a tooth out.
definitely agree here, misread original, thought vibes had been before belt fitted, having said that, not knowing because I have never done this job, but are any of the mountings touched during the job?
User avatar
dreamwarrioruk
Supreme Being
Posts: 2226
Joined: Wed Sep 28, 2005 7:39 pm
Location: york
Contact:

Re: Excessive vibration whilst stationary

Post by dreamwarrioruk » Wed May 20, 2009 8:50 pm

no you go no where nr the mounts when changing the cambelt.
mike, jo and emma
duncsuk

Re: Excessive vibration whilst stationary

Post by duncsuk » Wed May 20, 2009 9:22 pm

Thanks for the ideas ... I've spoken to the garage who changed the cambelt and they couldn't really give any reason. Didn't think it was a problem with the timing but agreed to take a look. I'm half expecting a 'they all do that sir' response ... so it's good to have a list of other points they can check while they have the car. Watch this space ...

PS : the only other 'change' was new 15/40W oil ? Could that have an effect ? I don't know what oil was in the car before the oil change.
scanner
Supreme Being
Posts: 7247
Joined: Wed Sep 19, 2007 10:20 pm
Location: Cambs

Re: Excessive vibration whilst stationary

Post by scanner » Wed May 20, 2009 10:44 pm

It should be 5w/30 or 10w/30.
duncsuk

Re: Excessive vibration whilst stationary

Post by duncsuk » Thu May 21, 2009 8:28 am

scanner wrote:It should be 5w/30 or 10w/30.
Thanks ... fair point .. though the FAQ section does mention that 'In standard UK operating temperatures you should use 10W-30 oil. In colder climes you should use 5W-30. If you find these difficult to obtain, then 10W/40 or even 15W/40 will do.'

Could it contribute to such effects as more vibration at idle and higher (more rattly) engine noise ?
fasthands

Re: Excessive vibration whilst stationary

Post by fasthands » Thu May 21, 2009 9:12 am

Sound to me that it is a tooth out, probably retarded the timing slightly. diesels will vibrate if retarded on the fuel timing. get it back asap so they wont argue its another problem. As it is a matter of doing the job just about allover again. :roll:
Locked

Return to “Techie Stuff”