It will only run when the engine is running, and the ambient temp outside is cold enough.
It will decide how much heat to produce from the coolant temp passing through it, but you will hear it start up... after hours of running our FBH is still running, just in standby, I think it will heat to about 70degC, and the engine takes it to 90deg.
If you PM me your email address I can send you a great word doc that I found on how to service it..
It will decide how much heat to produce from the coolant temp passing through it, but you will hear it start up... after hours of running our FBH is still running, just in standby, I think it will heat to about 70degC, and the engine takes it to 90deg.
If you PM me your email address I can send you a great word doc that I found on how to service it..
Can you feel any warmth in the air coming from the little exhaust under the nsf, its normal for it to howl for a few secs while it starts up, then turns to a blowpipe kinda sound..
Do I pull the fuse with the engine running?
I've pulled it out for a couple of mins without the keys in the ignition - nothing, didn't even try to start when I started the car up, can't hear the pump or anything. It's dead.
Was working perfectly until a few days ago. Any ideas?
I've pulled it out for a couple of mins without the keys in the ignition - nothing, didn't even try to start when I started the car up, can't hear the pump or anything. It's dead.
Was working perfectly until a few days ago. Any ideas?
Skynet
Well-Known Member
It will only fire up when less than 5 DegC and will then run until engine temp reaches approx 80DegC. Mine is always running lately because the thermostat is buggered and the temp remains lower than that. Try pulling fuse 5 when engine is cold, turning the ignition to pos 2 supplies the power to the FBH. So when the fuse is fitted the FBH should start up even without the engine running when outside temp is cold.
There are other threads which tell you how to short the Temp sensor that controls the FBH start up. The service document is in one of these threads, though dont ask me which one.
There are other threads which tell you how to short the Temp sensor that controls the FBH start up. The service document is in one of these threads, though dont ask me which one.
sijwhite
Active Member
Is that right? I though the whole point was that it would warm up the coolant and the interior without the engine running.
Thanks Dave, been looking at that thread.
I have the rear wheel arch liner off and have checked the pump works by applying 12v to it, all seems OK it clicks quite happily with power applied.
When I put fuse 5 back in, the FBH fan comes on and blows cold air from the exhaust... it does this for about a minute, stops for a couple of seconds and then does it again a couple of times before it gives up - at this point only a reset will make it try again.
At no point the FBH fuel pump being engaged during this sequence. Doesn't seem right. Any ideas?
Does anyone know if, following a reset the FBH fan will come on even if the temp sensor is telling it it's above the activation temperature? I don't know whether the fan coming on rules out the temp sensor or not?
I've been searching a lot, but there's lots of threads where people ask questions, and never talk about the resolution.
Thanks.
I have the rear wheel arch liner off and have checked the pump works by applying 12v to it, all seems OK it clicks quite happily with power applied.
When I put fuse 5 back in, the FBH fan comes on and blows cold air from the exhaust... it does this for about a minute, stops for a couple of seconds and then does it again a couple of times before it gives up - at this point only a reset will make it try again.
At no point the FBH fuel pump being engaged during this sequence. Doesn't seem right. Any ideas?
Does anyone know if, following a reset the FBH fan will come on even if the temp sensor is telling it it's above the activation temperature? I don't know whether the fan coming on rules out the temp sensor or not?
I've been searching a lot, but there's lots of threads where people ask questions, and never talk about the resolution.
Thanks.
dave21478
Active Member
The fan only comes on when it tries to light.
I would get the front wheel arch liner off to get at the FBH and check that the multi-plug is not corroded. This has the feed to the wee fuel pump in it, so if the contacts are oxidised there is perhaps no power getting to the pump. Use a 12v test lamp and see if it flashes.... iirc my multimeter was too slow to react the the FBH sending pulses to the pump.
Then try disconnecting the fuel hose from the fbh - its at the top and a real arse to reach. Pulse the pump and get someone to see if fuel comes through to eliminate a blockage in the pipe.
I would get the front wheel arch liner off to get at the FBH and check that the multi-plug is not corroded. This has the feed to the wee fuel pump in it, so if the contacts are oxidised there is perhaps no power getting to the pump. Use a 12v test lamp and see if it flashes.... iirc my multimeter was too slow to react the the FBH sending pulses to the pump.
Then try disconnecting the fuel hose from the fbh - its at the top and a real arse to reach. Pulse the pump and get someone to see if fuel comes through to eliminate a blockage in the pipe.
Can be made too, don't know if that was an option from new or not, not much hassle if you do want it too, keep thinking about modding ours to do that.. great in the winter, fire it up and go have a cuppa, 10 mins later nice and toasty..
Think their main purpose is to aid warming of the interior and engine during cold times, as the M47 engine amongst others is very efficient and produces little heat, disable it and see how much longer the temp gauge takes to get up when its below freezing... we had a vauxhall at work once that would take over 10 miles to get hot.. not a bad motor but slow at warming your feet!
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sijwhite
Active Member
I haven't got one sadly. I don't find the TD4 to be that slow in warming up though, certainly not 10 miles.
Think that was a bit of Vauxhall there maybe..
The FBH will have it up to 90deg in about 2 miles max..
