Campervan - Heater question

Conology

FFB Tabbert - Fiat Ducato - 1995.

The heater is making a screeching noise when I change gear down from 4th to 3rd, and 3rd to 2nd etc.
The noise only happens when the heater is turned on, otherwise the changing of gears up & down is quite smooth.
It doesn't happen moving up gears.

Just wondering
1) why this is happening and
2) is it causing any problem to the gear box.

Any advice please.

Thank you

kadman

Sounds possibly like maybe it could be the alternator screeching when the heater is on and the engine is at low revs.

My own alternator screeches at low revs, when a heater load is put on it, and goes when the revs are increased.

When engine is hot, no problem. has done for months, but I need to get it re built. Might be the same issue.

Mine is a VW T 25 by the way

johnayo

Might also be a loose fan belt screeching when the load come on.

kadman

johnayo wrote: »

Might also be a loose fan belt screeching when the load come on.

You beat me to it.:)

autumnalcore

Auxilliary belt tension as said, when its slipping like that it can polish/ wear the vee's in the pulleys with the result that a new belt slips too. So change the belt asap.

Conology

Thank you very much for your replies. Much appreciated.

If it's not the belt or tensioner next call is the pulley bearing.

Conology

Sir Liamalot wrote: »

If it's not the belt or tensioner next call is the pulley bearing.

I'm not mechanically minded .Haven't heard of a pulley bearing.
Where could I get a replacement and who might fit it etc.

Is it risky to drive with this problem ??
Does it affect the gear box or what damage can I do by continuing to drive it like this as we're going on a 2 week trip next month.

Odelay

Conology wrote: »

I'm not mechanically minded .Haven't heard of a pulley bearing.
Where could I get a replacement and who might fit it etc.

Is it risky to drive with this problem ??
Does it affect the gear box or what damage can I do by continuing to drive it like this as we're going on a 2 week trip next month.

Take it to a mechanic and get it sorted before your trip next month.

Conology

Odelay wrote: »

Take it to a mechanic and get it sorted before your trip next month.

Will do - but would still like to know the answer to my questions
Thanks

The belt pulleys are riding axes guided by bearings. The have a finite lifespan proportional to belt tension and frequency of use.

If they're chowdered it needs to be replaced.
Simple job for a competent mechanic...good luck finding one! They can organise a rebuild. More than likely bearings are ok and a new tensioned belt will solve it.
It's a kindov thing that breaks slowly so it's not urgent but needs doing or it'll chew up your belt eventually.

I always carry a spare fanbelt.
The gearbox has nothing to do with it.
The issue is more apparent at low RPM.

autumnalcore

Conology wrote: »

I'm not mechanically minded .Haven't heard of a pulley bearing.
Where could I get a replacement and who might fit it etc.

Is it risky to drive with this problem ??
Does it affect the gear box or what damage can I do by continuing to drive it like this as we're going on a 2 week trip next month.

The fact that it only happens with a heavy electrical load means the most likely thing is auxiliary belt / belt tension. Belts are cheap consumables they are replaced routinely. The belt is less than 20 euros and very easy to change on most of the ducato engines. If it not cured by the belt you can go look for more sinister causes like alternator / water pump bearings, timing tensioner etc.

Conology

Sir Liamalot wrote: »

The belt pulleys are riding axes guided by bearings. The have a finite lifespan proportional to belt tension and frequency of use.

If they're chowdered it needs to be replaced.
Simple job for a competent mechanic...good luck finding one! They can organise a rebuild. More than likely bearings are ok and a new tensioned belt will solve it.
It's a kindov thing that breaks slowly so it's not urgent but needs doing or it'll chew up your belt eventually.

I always carry a spare fanbelt.
The gearbox has nothing to do with it.
The issue is more apparent at low RPM.

Thanks Liam, ill get it done next week if possible & get the spare fan belt too

The spare belt doesn't have to be new it just has to get you home. Just keep the old one.

Conology

autumnalcore wrote: »

The fact that it only happens with a heavy electrical load means the most likely thing is auxiliary belt / belt tension. Belts are cheap consumables they are replaced routinely. The belt is less than 20 euros and very easy to change on most of the ducato engines. If it not cured by the belt you can go look for more sinister causes like alternator / water pump bearings, timing tensioner etc.

Thank you

Conology

Sir Liamalot wrote: »

The spare belt doesn't have to be new it just has to get you home. Just keep the old one.

Thanks Liam

Conology

Hi all,
Just to follow up on this.
I brought the campervan to a mechanic this morning.
He said the fan-belt was quite tight, but he managed to get a bit of a squeeze onto it.
Driving home then I tested it out again with the Heater running and there was no further screeching, so fingers crossed the problem is solved.
Thank you all for your help.

CJhaughey

Conology wrote: »

Hi all,
Just to follow up on this.
I brought the campervan to a mechanic this morning.
He said the fan-belt was quite tight, but he managed to get a bit of a squeeze onto it.
Driving home then I tested it out again with the Heater running and there was no further screeching, so fingers crossed the problem is solved.
Thank you all for your help.

Get a new belt! The added pressure can do harm to your alternator bearings.
The reason it's screeching was that it has worn and is narrower than a new belt.
A belt isn't expensive and will take a lot of pressure off your bearings.

kadman

Sounds like the alternator bearings may well already be kaputt.
The additional tighten on an already tight belt is just putting additional
pressure on the worn bearings, taking up the slack in the bearings as opposed to the
belt tension.

But you will know in a very short space of time, if this is the case. keep an eye on it,
as a rebuild is only about 75 euro, which is a lot less than the cost of a new one.
Good luck with it.

Conology

kadman wrote: »

Sounds like the alternator bearings may well already be kaputt.
The additional tighten on an already tight belt is just putting additional
pressure on the worn bearings, taking up the slack in the bearings as opposed to the
belt tension.

But you will know in a very short space of time, if this is the case. keep an eye on it,
as a rebuild is only about 75 euro, which is a lot less than the cost of a new one.
Good luck with it.

When you say "Rebuild" - can you explain.
Thank you

kadman

Alternator rebuild would basically give you a reconditioned unit , with some level
of guarantee, depending on which reputable outfit you chose.

Anywhere from 3 months to 12 months.

This would normally cover rectifier packs, brushes,bushings, bearings ect.

These are the run of the mill things that give trouble.

Inspection and up front quotes of the alternator when you bring in the unit

vary from free to very small money.

Last unit I had done was 60 euro 2 or 3 year ago still going strong.