V6 Cambelt Replacement
Moderators: Doone, westonwarrior
-
- Bongolier
- Posts: 140
- Joined: Sat Jun 28, 2008 9:05 am
- Location: Hitchin, Herts
V6 Cambelt Replacement
Hello. We have a year 2000 V6 with about 50,000 KM. As far as I'm aware it has not had a new cambelt. Can anyone advise on any of the following:
Is it over cautious to change it now?
Is it foolhardy to attempt it yourself? (my mechanical level is only average e.g quite happy with changing brakes but wouldn't want to touch a head gasket...)
Should the tensioning mechanism be replaced at the same time? (It's expensive isn't it?)
Is there any other job that should sensibly be incorporated with cambelt renewal i.e. "While you're doing that replace 'part x' as it's a b**** otherwise...."
Can anyone reccomend a reputable garage / mechanic who might undertake such a job? We are near Hitchin, just North of London.
Very roughly, what could we expect to pay?
Thanks for any help you can provide, Dave.
Is it over cautious to change it now?
Is it foolhardy to attempt it yourself? (my mechanical level is only average e.g quite happy with changing brakes but wouldn't want to touch a head gasket...)
Should the tensioning mechanism be replaced at the same time? (It's expensive isn't it?)
Is there any other job that should sensibly be incorporated with cambelt renewal i.e. "While you're doing that replace 'part x' as it's a b**** otherwise...."
Can anyone reccomend a reputable garage / mechanic who might undertake such a job? We are near Hitchin, just North of London.
Very roughly, what could we expect to pay?
Thanks for any help you can provide, Dave.
- maxheadroom
- Supreme Being
- Posts: 1950
- Joined: Wed Feb 28, 2007 6:37 pm
- Location: Gloucester
Re: V6 Cambelt Replacement
Yes change the tensioning mechanism. As for the cost I can't help there.BongoBonkers wrote:Should the tensioning mechanism be replaced at the same time? (It's expensive isn't it?)
Re: V6 Cambelt Replacement
Hesitate to say that it IS over cautious, because I wouldn't want you to then have a problem and come knocking on my doorBongoBonkers wrote:Hello. We have a year 2000 V6 with about 50,000 KM. As far as I'm aware it has not had a new cambelt. Can anyone advise on any of the following:
Is it over cautious to change it now?
Is it foolhardy to attempt it yourself? (my mechanical level is only average e.g quite happy with changing brakes but wouldn't want to touch a head gasket...)
Should the tensioning mechanism be replaced at the same time? (It's expensive isn't it?)
Is there any other job that should sensibly be incorporated with cambelt renewal i.e. "While you're doing that replace 'part x' as it's a b**** otherwise...."
Can anyone reccomend a reputable garage / mechanic who might undertake such a job? We are near Hitchin, just North of London.
Very roughly, what could we expect to pay?
Thanks for any help you can provide, Dave.

When we ordered our conversion, ours had 62,000 km on the clock and the excellent dealer-converter we bought from advised against premature change of the cambelt - probably quite rightly, when I now think about it with hindsight. Can't remember off-hand what the (significantly higher) recommended cambelt change mileage is but, of course, even that will have been set conservatively, with a good safety margin in addition.
However, because the dealer in quiestion, quite rightly, covers himself by a formal declaration that the displayed mileage cannot be guaranteed, and because I'm a worry-guts, I decided to get it changed, anyway!
Thought I would get it done locally, by northern Bongo gurus, Wheelquick, once I had taken possession of the van. However, a quick intake of breath there (and a bad experience they had apparently had, changing just one on a V6 up until then - last October), took me back to the supplying dealer who was still working on the camper conversion. Wheelquick had told me they had needed to spend about £250 on a special "puller" to finish the job on the V6 they did - just for starters. My dealer though, said yes, we've done plenty and have got the tools, so if you insist - and so it was done, £195.
I've now got top hose coolant leak problems, apparently due to a screwdriver nick when they were re-fitting one of the hose clips as part of that job. The leak was very slow at first, and it wasn't until it suddenly spread under system pressure and dropped the header tank level far enough to recently set off my low coolant alarm, that I could find it. Just got the replacement hose, and am now waiting for Wheelquick to fit it - so, yes I've got a new cambelt but it was not a joyous experience!
One other relevant point, which I've not been able to get answered yet, is whether or not the J5 V6 engine is an "interference" engine, anyway. If it isn't, then a sudden cambelt failure would only stop the engine but without catastrophic result. An interference engine design achieves compactness by reducing cylinder length vs piston stroke, so that the upward travel of the piston overlaps the space occupied by valves during their downward travel - it "interferes." Fine, while the cambelt is keeping the valves properly closed while the piston is uppermost in its travel, and vice versa. Not so good, if the cambelt fails leaving valves open inside cylinders for pistons to collide with, at which point goodbye bank balance. Non-interfering engines, and there are still plenty, just come to a dignified stop, without any metal bashing.
Does anybody know the answer? The Bongo diesel is definitely an interferer, and I suspect the V6 J5 probably is, or it might be hard to shoehorn in (although, with inclined cylinders perhaps not) - it would be nice to know.
2001-V6-LPG-AFT-black on silver-Imperial Purbeck camper
(Ron miel=honey rum from the Canaries)
(Ron miel=honey rum from the Canaries)
Re: V6 Cambelt Replacement
I guess that's not necessarily strictly accurate. Anyway, the principle is that the valve heads intrude into cylinder volume alternately occupied by pistons during the upper part of their travel (always assuming it's not an inverted engine, that isRon Miel wrote:.......An interference engine design achieves compactness by reducing cylinder length vs piston stroke, so that the upward travel of the piston overlaps the space occupied by valves during their downward travel....

2001-V6-LPG-AFT-black on silver-Imperial Purbeck camper
(Ron miel=honey rum from the Canaries)
(Ron miel=honey rum from the Canaries)
- Simon Jones
- Supreme Being
- Posts: 9341
- Joined: Mon Aug 29, 2005 3:34 pm
- Location: Salisbury (ish), Wiltshire
Re: V6 Cambelt Replacement
I'm no expert on cambelts, but I'm led to believe that mileage alone is not the only factor to determine when it should be replaced: the age is equally important. The first site I found by Google-ing 'cambelt replacement' was this one:
http://www.cambelters.co.uk/
They suggest 4 - 5 years is the typical life expectancy. So, if the previous owners have followed that recommendation, then it will have been changed once & will be due for it's second one about now. If not, then it's definitely over-due now. We sold a Fiesta last year with less than 60K on the clock - but the belt was 12 years old. Prior to that we had a diesel fiesta that snapped its belt just over a year after it was replaced. Three bent valves & £500 later......
http://www.cambelters.co.uk/
They suggest 4 - 5 years is the typical life expectancy. So, if the previous owners have followed that recommendation, then it will have been changed once & will be due for it's second one about now. If not, then it's definitely over-due now. We sold a Fiesta last year with less than 60K on the clock - but the belt was 12 years old. Prior to that we had a diesel fiesta that snapped its belt just over a year after it was replaced. Three bent valves & £500 later......
Re: V6 Cambelt Replacement
Probably makes sense, Simon, but never forget that http://www.cambelters.co.uk has a very vested interest in persuading us to change cambelts. I think that, in the end, the sensible approach is probably, if it's an interference engine, err on the side of caution. If it isn't, well it's not so critical, so if it's not broke don't fix it until the specified mileage. You don't happen to know whether the J5 V6 is or isn't, do you? Can't find it online, so if nobody comes up with a credible (quoting source) answer here, I think I might write to HiroshimaSimon Jones wrote:I'm no expert on cambelts, but I'm led to believe that mileage alone is not the only factor to determine when it should be replaced: the age is equally important. The first site I found by Google-ing 'cambelt replacement' was this one:
http://www.cambelters.co.uk/
They suggest 4 - 5 years is the typical life expectancy. So, if the previous owners have followed that recommendation, then it will have been changed once & will be due for it's second one about now. If not, then it's definitely over-due now. We sold a Fiesta last year with less than 60K on the clock - but the belt was 12 years old. Prior to that we had a diesel fiesta that snapped its belt just over a year after it was replaced. Three bent valves & £500 later......

2001-V6-LPG-AFT-black on silver-Imperial Purbeck camper
(Ron miel=honey rum from the Canaries)
(Ron miel=honey rum from the Canaries)
- Simon Jones
- Supreme Being
- Posts: 9341
- Joined: Mon Aug 29, 2005 3:34 pm
- Location: Salisbury (ish), Wiltshire
Re: V6 Cambelt Replacement
Not sure on that question, but did find a website that gives some history of the Mazda V6 engine including J5:
http://autospeed.com/cms/A_2877/article.html
http://autospeed.com/cms/A_2877/article.html
Re: V6 Cambelt Replacement
Yes, saw that while I nosed around - an interesting read for anybody that hasn't seen it. No confirmation re interferer or not though, as you imply.Simon Jones wrote:Not sure on that question, but did find a website that gives some history of the Mazda V6 engine including J5:
http://autospeed.com/cms/A_2877/article.html
.
2001-V6-LPG-AFT-black on silver-Imperial Purbeck camper
(Ron miel=honey rum from the Canaries)
(Ron miel=honey rum from the Canaries)
Re: V6 Cambelt Replacement
According to this site http://929.sentia.ru/english.htm it is an interference engine it also gives you step by step instruction with diagrams on how to change cam belt.
- dandywarhol
- Supreme Being
- Posts: 5446
- Joined: Mon Dec 19, 2005 10:18 pm
- Location: Edinburgh
Re: V6 Cambelt Replacement
The UK AUTODATA info also classifies the 929 as an INTERFERENCE engine - liable to bend the valves if the belt snaps.
Also says no specialist tools required and 2.3 hours to do (on a car)
Also says no specialist tools required and 2.3 hours to do (on a car)
Whale oil beef hooked
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
Re: V6 Cambelt Replacement
Hi,
I had mine done before taking delivery. The mechanic there (who I have great respect for) said it was a long job as it's hard to get at.
I'd personally get mine done every 4-5 years or 60k, the manual says longer on the mileage but the damage that would be caused by not doing it is huge. A guy at work has had cambelt problems on his past 3 cars, cheapest was £1500, current one is standing at £2400 and rising. I have no idea why he has such a love for upper engine rebuilds but I'm not asking as it's a very sore point
I had mine done before taking delivery. The mechanic there (who I have great respect for) said it was a long job as it's hard to get at.
I'd personally get mine done every 4-5 years or 60k, the manual says longer on the mileage but the damage that would be caused by not doing it is huge. A guy at work has had cambelt problems on his past 3 cars, cheapest was £1500, current one is standing at £2400 and rising. I have no idea why he has such a love for upper engine rebuilds but I'm not asking as it's a very sore point
