Changed front tyres, new cambelt, less acceleration?

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digitalgypsy
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Changed front tyres, new cambelt, less acceleration?

Post by digitalgypsy » Thu Sep 13, 2012 5:46 pm

Hello chaps,
I've just had new front tyres put on and also had the cambelt changed. I noticed on the way home from the garage that the Bongo doesn't accelerate as easy. I mainly noticed that between 20-40mph I had to press the pedal a little harder to accelerate. Is that kind of thing normal for new tyres or after the cambelt is changed??

Thanks for any help,
Steve
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dave_aber
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Re: Changed front tyres, new cambelt, less acceleration?

Post by dave_aber » Thu Sep 13, 2012 5:47 pm

Is your Bongo a 4WD?
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digitalgypsy
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Re: Changed front tyres, new cambelt, less acceleration?

Post by digitalgypsy » Thu Sep 13, 2012 6:10 pm

Hey Dave,
Yes it is.
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dave_aber
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Re: Changed front tyres, new cambelt, less acceleration?

Post by dave_aber » Thu Sep 13, 2012 6:11 pm

What size / type / wear are your rear tyres, and what size / type are your new front tyres?
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Re: Changed front tyres, new cambelt, less acceleration?

Post by digitalgypsy » Thu Sep 13, 2012 6:14 pm

Front: 195/70
Rear: 215/65

The front ones were also 195/70 before swapping. They are just a different brand now.
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Re: Changed front tyres, new cambelt, less acceleration?

Post by mikexgough » Thu Sep 13, 2012 6:20 pm

hope they timed the cambelt right... it will run a notch out safely but could be why Bongo seems a bit "sluggish"...
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dave_aber
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Re: Changed front tyres, new cambelt, less acceleration?

Post by dave_aber » Thu Sep 13, 2012 6:27 pm

As the tyres look on the face of it to be OK, it may well be a cam timing issue. I'd ask them to re-check the timing for you.
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Re: Changed front tyres, new cambelt, less acceleration?

Post by digitalgypsy » Thu Sep 13, 2012 6:28 pm

b*st*ds. surely you shouldn't have to worry about the cambelt being changed properly if it's a good garage? :cry:
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Re: Changed front tyres, new cambelt, less acceleration?

Post by dave_aber » Thu Sep 13, 2012 6:29 pm

Could just be an honest mistake. To be honest, I doubt you'd 'feel' sluggishness caused by tyre sizes - but you really will feel it if the timing is out by a tooth.
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Re: Changed front tyres, new cambelt, less acceleration?

Post by digitalgypsy » Thu Sep 13, 2012 6:30 pm

back to the garage it goes then, already waited over 6 hours today. thanks for advice though :)
digitalgypsy
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Re: Changed front tyres, new cambelt, less acceleration?

Post by digitalgypsy » Thu Sep 13, 2012 6:34 pm

Man...I was planning to take the Bongo to Celtic Motorhomes tomorrow to get some furniture fitted. If the timing is out, do you think it's bad to take on a long trip before having it checked?
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dave_aber
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Re: Changed front tyres, new cambelt, less acceleration?

Post by dave_aber » Thu Sep 13, 2012 6:53 pm

In theory, if nothing went bang when it as first started, then nothing's going to go bang now.

But, I wouldn't be keen on using high revs, just in case the clearance between piston and valve is marginal.....

I've not done a timing belt on a bongo myself, but it is possible on some engines to have a similar timing issue if the tensioner is slack - and I wouldn't advise driving at all with a slack tensioner. Don't know if it's feasible to leave the tensioner slack on the Bongo engine though.
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Re: Changed front tyres, new cambelt, less acceleration?

Post by digitalgypsy » Thu Sep 13, 2012 7:01 pm

Ok thanks for the valuable advice Dave. Looks like trip to Wales is postponed #-o
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Re: Changed front tyres, new cambelt, less acceleration?

Post by Northern Bongolow » Thu Sep 13, 2012 7:39 pm

if the front tyres are new and the rears are old you could just be fighting the transfer box, when all are new in the sizes above the rears are actually 6mm larger dia, or 18mm circumference bigger, if you have new fronts and well worn rears the difference could be nil, or even the fronts larger, this may make it feel odd.
i would check the depth of tread on the rear, and the pressures.
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