Serpentine Belt Woes
Discussion
Attempting to replace the Serpentine Belt on my Mazda 6 2008 2.5 Petrol 80K Miles
Never done one before.
I cannot get the new one to fit.
I have refitted the old one, so am routing it correctly.
It has an auto-tensioner which I have rotated 90 deg. which I believe is the full extent of the movement.
The new Belt is a bit shorter than the old one but I presume they stretch when they wear so is to be expected?
I have checked several Suppliers and measured the new one the best I can. Should be 2285mm. I measured 2280mm
The old one is about 2300mm
I presume I shouldn't need to lever it into position?
The final pulley I am trying to get it on is approx 70mm Pulley
Any tips or tricks before I give up and pass it to a professional please?
I feel a bit useless
Never done one before.
I cannot get the new one to fit.
I have refitted the old one, so am routing it correctly.
It has an auto-tensioner which I have rotated 90 deg. which I believe is the full extent of the movement.
The new Belt is a bit shorter than the old one but I presume they stretch when they wear so is to be expected?
I have checked several Suppliers and measured the new one the best I can. Should be 2285mm. I measured 2280mm
The old one is about 2300mm
I presume I shouldn't need to lever it into position?
The final pulley I am trying to get it on is approx 70mm Pulley
Any tips or tricks before I give up and pass it to a professional please?
I feel a bit useless
If you think the old belt seemed to fit correctly, replace it with one that matches it, not what the internet tells you the part should have been. Can you read the part number from the old one? If so, that will give you the exact size you're looking for.
20+mm is quite a lot of difference. Bearing in mind you need a certain amount of slack to get the belt on, it's not surprising the new belt is too short if the old was was correct.
PS poly vee belts don't stretch much in use. The flat face is very stiff and won't stretch. This is the part that defines the belt length. As the ribs wear, the flat face will get closer to the ribbed pulleys which will make the belt appear to stretch slightly, but it's not a big effect.
20+mm is quite a lot of difference. Bearing in mind you need a certain amount of slack to get the belt on, it's not surprising the new belt is too short if the old was was correct.
PS poly vee belts don't stretch much in use. The flat face is very stiff and won't stretch. This is the part that defines the belt length. As the ribs wear, the flat face will get closer to the ribbed pulleys which will make the belt appear to stretch slightly, but it's not a big effect.
Edited by GreenV8S on Saturday 29th September 17:00
Met this issue with RRC belt on another forum. The one listed by all the usual suppliers was too short.
After a lot of searching it transpired to be a superseded part number BUT that belt wasn't the same for all V8s, some requiring a longer belt.
Sorted by measuring the old belt & buying one of the correct dimensions.
After a lot of searching it transpired to be a superseded part number BUT that belt wasn't the same for all V8s, some requiring a longer belt.
Sorted by measuring the old belt & buying one of the correct dimensions.
Should be a 2285 on this engine.
What happened to this btw: https://www.pistonheads.com/gassing/topic.asp?h=0&...
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What happened to this btw: https://www.pistonheads.com/gassing/topic.asp?h=0&...
?
Evoluzione said:
Should be a 2285 on this engine.
What happened to this btw: https://www.pistonheads.com/gassing/topic.asp?h=0&...
?
2285 is what I read on the Part Suppliers and Belt Manufactures Sites and what I ordered.What happened to this btw: https://www.pistonheads.com/gassing/topic.asp?h=0&...
?
It just won't go on?
Still living with the other thing. Still fairly intermittent.
I am getting overheating (goes down with higher Revs/same Road Speed) which is why I am replacing the Belt.
I got stuck in Traffic and the Overheating/No Throttle response seem like they may be related.
The Service Manual indicates that the ECU cuts Throttle to prevent overheat.
Managing the overheat by turning up the Cabin Temp at the moment.
imck said:
2285 is what I read on the Part Suppliers and Belt Manufactures Sites and what I ordered.
It just won't go on?
Still living with the other thing. Still fairly intermittent.
I am getting overheating (goes down with higher Revs/same Road Speed) which is why I am replacing the Belt.
I got stuck in Traffic and the Overheating/No Throttle response seem like they may be related.
The Service Manual indicates that the ECU cuts Throttle to prevent overheat.
Managing the overheat by turning up the Cabin Temp at the moment.
If you suspect the belt may be slipping it would be squealing like a pig.
It just won't go on?
Still living with the other thing. Still fairly intermittent.
I am getting overheating (goes down with higher Revs/same Road Speed) which is why I am replacing the Belt.
I got stuck in Traffic and the Overheating/No Throttle response seem like they may be related.
The Service Manual indicates that the ECU cuts Throttle to prevent overheat.
Managing the overheat by turning up the Cabin Temp at the moment.
If you suspect the belt may be slipping it would be squealing like a pig.
finlo said:
If you suspect the belt may be slipping it would be squealing like a pig.
It is not squealing. The Water Pump is driven from the smooth side of the belt - don't know if this is common?I am getting overheating. The Temp goes back to halfway if I drop a Gear or two but maintain the same Road Speed.
My Logic is Water Pump or Water Pump Drive.
Someone on here suggested Impeller rusted away but I have clean Coolant and guess it is the original Long Life (11 Years).
I am trying the Water Pump Drive first. The Original Belt has a lot of cracks and is very shiny.
I turned the Water Pump by hand once I had removed the Belt. Turning freely and no play.
Tiny bit of play in the idler Pulleys.
Other suggestions on the overheating very welcome.
imck said:
Other suggestions on the overheating very welcome.
The smooth side of the belt has much less grip than the grooved side so it's not impossible that it is slipping. If you suspect the belt is slipping, you could try applying belt dressing spray. If you get stuck, you can rub the belt with a block of soap (engine stopped) which acts as a friction improver. But if the belt surface is cracked, it will need replacing anyway.It's difficult to understand the thought process that led to ordering a new belt which as long as the stretched worn out one.
The one you have is correct, you just have to work out the method of fitting it.
This is very unlikely to be anything to do with your 'overheating' issue, how exactly is this manifesting itself?
The one you have is correct, you just have to work out the method of fitting it.
This is very unlikely to be anything to do with your 'overheating' issue, how exactly is this manifesting itself?
227bhp said:
It's difficult to understand the thought process that led to ordering a new belt which as long as the stretched worn out one.
The one you have is correct, you just have to work out the method of fitting it.
This is very unlikely to be anything to do with your 'overheating' issue, how exactly is this manifesting itself?
I have the Factory Service Manual which does not cover the Belt change in much detail.The one you have is correct, you just have to work out the method of fitting it.
This is very unlikely to be anything to do with your 'overheating' issue, how exactly is this manifesting itself?
I watched a couple of Youtube Videos of the Belt being changed on the Mazda 6. Their Belts went on with a little persuasion.
The old Belt sits within the Tolerance Marks on the Tensioner.
The Belt is £15. If it fits properly and works great. If not I will get my Garage to change when in for MOT/Service next Month.
I have fixed Printers for many Years, so very familiar with fitting/adjusting Drive Belts albeit a lot smaller and toothed.
Overheating
Commute Home shows it the most
5 Mins to Motorway and the Car is midway on the Temp Gauge
20-25 Mins 20-40 MPH on congested but moving Motorway. Still midway
Join fairly fast moving Motorway 50-70 MPH for 10-15 Mins (2Kish Revs) and it will start to overheat after 5 Mins or so.
Drop to 4th/5th but maintain the same Road Speed and the Temp goes back to midway.
Leave Motorway 20-30 MPH for 5-10 Mins. Having to turn the Cabin Temp up to lower Coolant Temp if it starts overheating.
Commute to Work in the Morning roughly the same speed pattern.
Does not start to overheat until the last 5 Mins usually as I am leaving the Motorway.
No sign of any leaks. Coolant looks clean in the Expansion Tank and top of Rad. Both Fans operate.
Probably not related but AC stops working after about 30 Mins Operation as well.
Car is a bit jerky in Traffic and slight hiccup at 3Kish
After a bit of searching for various permutations of your car when I tried 'Mazda 6 2008 2.5 ribbed belt' I came across this website:
https://www.buycarparts.co.uk/mazda/6-estate-gh/28...
It lists several different makes of belt at 2285mm which you say are too short.
It also lists one belt - Bosch - at 2300mm which is the same length as yours.
So it appears two lengths are in use on this engine.
I'd suggest speaking to the parts dept of a franchised Mazda dealer with your VIN and engine numbers to see if they can shed some light on this.
https://www.buycarparts.co.uk/mazda/6-estate-gh/28...
It lists several different makes of belt at 2285mm which you say are too short.
It also lists one belt - Bosch - at 2300mm which is the same length as yours.
So it appears two lengths are in use on this engine.
I'd suggest speaking to the parts dept of a franchised Mazda dealer with your VIN and engine numbers to see if they can shed some light on this.
Edited by paintman on Sunday 30th September 02:10
Ok, so to sum up it's getting hot after a motorway run. This rules out fans (even though you said they are working anyhow), but points to the possibility of the radiator or aircon condensor being corroded (externally) or blocked as it isn't working properly. Can you shine a torch in and check the condition of it and the aircon rad as that will be fitted to the front of it?
If the tension indicator was halfway then whilst the old belt was past its best it was still doing the job, you could also get hold of the pump pulley and see if it turns with the belt on.
You can ring Mazda parts, quote the reg and they will give you the correct part No. for your belt.
Mazda fit their own special magic coolant which whilst they say must be changed at xxxxx miles actually seems to last the life of the engine, internal corrosion is unlikely.
Also on the suspect list is the thermostat, although again unlikely as they normally fail open so way down the list of possibles.
If the tension indicator was halfway then whilst the old belt was past its best it was still doing the job, you could also get hold of the pump pulley and see if it turns with the belt on.
You can ring Mazda parts, quote the reg and they will give you the correct part No. for your belt.
Mazda fit their own special magic coolant which whilst they say must be changed at xxxxx miles actually seems to last the life of the engine, internal corrosion is unlikely.
Also on the suspect list is the thermostat, although again unlikely as they normally fail open so way down the list of possibles.
paintman said:
After a bit of searching for various permutations of your car when I tried 'Mazda 6 2008 2.5 ribbed belt' I came across this website:
https://www.buycarparts.co.uk/mazda/6-estate-gh/28...
It lists several different makes of belt at 2285mm which you say are too short.
It also lists one belt - Bosch - at 2300mm which is the same length as yours.
So it appears two lengths are in use on this engine.
I'd suggest speaking to the parts dept of a franchised Mazda dealer with your VIN and engine numbers to see if they can shed some light on this.
Thanks Paintman.https://www.buycarparts.co.uk/mazda/6-estate-gh/28...
It lists several different makes of belt at 2285mm which you say are too short.
It also lists one belt - Bosch - at 2300mm which is the same length as yours.
So it appears two lengths are in use on this engine.
I'd suggest speaking to the parts dept of a franchised Mazda dealer with your VIN and engine numbers to see if they can shed some light on this.
Edited by paintman on Sunday 30th September 02:10
That is where I bought the Belt from. They also show one that is 2900mm
The current Belt is within wear limit on the Tensioner Indicator
I will fit the other one I have just ordered and see how that is.
Here's what I suggest you do. Cut your old belt so it's a string not a belt and fit it into position on the pulleys as tightly as you can get it and mark where the ends overlap. Measure. This is the shortest belt length you're going to be able to fit with a bit of levering. Buy a belt a tad longer than that.
imck said:
I presume I shouldn't need to lever it into position?
Yes you may have to and as long as you're careful and don't use sharp edged screwdrivers you should be fine. Bicycle tyre levers or even an old spoon handle might do the trick. It's a bit like fitting a tyre over a rim. Needs a pull to get it over the lip but all good once it's sitting on the bead.227bhp said:
Ok, so to sum up it's getting hot after a motorway run. This rules out fans (even though you said they are working anyhow), but points to the possibility of the radiator or aircon condensor being corroded (externally) or blocked as it isn't working properly. Can you shine a torch in and check the condition of it and the aircon rad as that will be fitted to the front of it?
If the tension indicator was halfway then whilst the old belt was past its best it was still doing the job, you could also get hold of the pump pulley and see if it turns with the belt on.
You can ring Mazda parts, quote the reg and they will give you the correct part No. for your belt.
Mazda fit their own special magic coolant which whilst they say must be changed at xxxxx miles actually seems to last the life of the engine, internal corrosion is unlikely.
Also on the suspect list is the thermostat, although again unlikely as they normally fail open so way down the list of possibles.
The Rad is not easily visible but what I can see between the Fan Blades looks in good condition.If the tension indicator was halfway then whilst the old belt was past its best it was still doing the job, you could also get hold of the pump pulley and see if it turns with the belt on.
You can ring Mazda parts, quote the reg and they will give you the correct part No. for your belt.
Mazda fit their own special magic coolant which whilst they say must be changed at xxxxx miles actually seems to last the life of the engine, internal corrosion is unlikely.
Also on the suspect list is the thermostat, although again unlikely as they normally fail open so way down the list of possibles.
The Condensor is a bit sad in the bottom section where the Lower Grille is. Mix of collapsing Fins and no Fins (probably the pressure washing at the local Hand Car Wash)
Top section looks in good condition.
I only tried to turn the Water Pump Pulley by hand but could not get to move.
Not a lot of room to get any force on it. The Engine/Belt/Pulleys are stone cold if that makes a difference.
I had the AC checked by a Mobile AC Man back in July due to it stopping after 30 Mins
He suspected the Clutch failing with heat but I asked him to regas anyway
Recovered 250ml. Filled with 500ml I think. AFter that he said that was likely to have been the problem.
Worked OK for a day or two then back to stopping after 30 Mins.
Commute is normally 40 Mins, so has not been top of my list to sort.
The Tensioner is in the 'Good' Zone with the old Belt.
I will give Mazda a call and see if they can advise on the correct Belt Length.
Failing that I will try the longer Belt and check the Tensioner markings are within Tolerance.
Suspect now that the Belt is not the cause of the problem but was due a changed and not too expensive.
I have the FL22 Coolant Label on the Rad Cap. 11 Year Life according to the Service Schedule
Have you confirmed the rad fan works? Ur air con fault sounds very much like a failed fan, and with the overheating at higher loads the engine may need the rad fan to give extra cooling rather than just the forced air from motorway speeds especially if it’s partiall blocked on the radiator
Elliot2000 said:
Have you confirmed the rad fan works? Ur air con fault sounds very much like a failed fan, and with the overheating at higher loads the engine may need the rad fan to give extra cooling rather than just the forced air from motorway speeds especially if it’s partiall blocked on the radiator
Both Fans workIt's definitely a 2285 on this engine. I'm assuming you're trying to get the last bit of belt onto one of the smooth pulleys and not a ribbed one? It shouldn't be difficult, but you can take off the top r/h idler easy enough to help.
As per above, check air-con condenser hasn't collapsed or is blocked stopping flow to the rad.
As per above, check air-con condenser hasn't collapsed or is blocked stopping flow to the rad.
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