Well i've finally got the cooling flaps with a bellows thermostat re-installed into my engine ( type 1 ) Also the missing 'Hoover' bracket, 'stove pipe' and rear lower air deflector plates l/h & r/h have been fitted. Also recently replaced the thermostatically operated device in the air cleaner. My question is,..... do the flaps normally remain closed on a cold / freezing day like today ?. After a 10 mile drive i checked the thermostat and it was in the closed position. Engine temperature normal, on the cool side really. Opinions from experienced 'flappers' much appreciated.
can you show the type of thermostat that you used ...there is two types i believe ....and one can stay shut if it fails and overheats your engine badly . But if it's new it's probably OK .....is it the bellows type ?
Really you need the lower curved tins in place (if that’s what you’re missing), as they form hot air ducts to the rear of the van. If the RH one is missing, I can imagine the thermostat not getting longer as any hot air would just be blown away. Not really good for the flaps to be shut all the time. Also, assume the stat is adjusted correctly?
As i said, the rear lower air deflector plates have been fitted, l/h & r/h. All tin intact Pretty sure the stat is set properly, my question is, is it normal for the flaps to stay closed in very cold to freezing conditions?.
Did you test the thermostat in boiling water before fitting it, to prove it does actually expand as it should. I did that with mine as I refitted the old one and wanted to be sure it worked properly.
I didn't fit it ,but it was checked with a hot air gun. I could get under and check it tomorrow with a hair dyer in situ,.. but i don't think there's a problem because i drove about 10 miles with no temperature or running issues, i checked the dipstick and it felt normal but as i say the stat was fully closed, i'm presuming down to near freezing air temperature.
Sorry, missed that. I would expect it to open fairly soon, once the engine had warmed up. May be that you weren’t quick enough nipping round the back to see. If it was really cold, may have contracted again once the engine was switched off.
If you only drove it gently then the flaps might not open on a cold day but..... There is an adjustment procedure which involves checking the flaps just close when its cold and the bracket is slid up and down and you can also partly unscrew the thermostat on the threaded rod if you have to.. Thats why theres a slot in the bracket. Just dont yank on the rod. Mine pinged out once or twice.. you can just about get it back with the fanhousing on the engine in the bus but it involves screwdrivers as levers to lift the fanhousing and precision use of force. Ratwell.com quotes cold length of thermostat somewhere.. My long suffering threaded rod tended to catch on the cylinder heads and it can be worth checking that it isnt sticking, and the top of the thermostat isnt rubbing on the bracket . There was a particular fore and aft angle of the bracket that was best.. sort of +/- 5 degrees from vertical. On my new engine the holes in the EMPI heads are properly cleaned out.
Got under the van today and checked the bellows stat with a hair dryer and laser temp gun , opened at 70 C .
I’ve had my van 15 yrs. 18 months ago it had a new engine and I asked for the thermostat and associated bits to be installed. I don’t notice much difference in the summer at all but in the winter it warms up so much better. I’ve been out today. 3 degrees. Within a mile there is warm air at the dash. Say I drive a couple of miles at 30mph and switch it off.... the engines nice and warm. On the old engine without the stat it would have been really quite cool still.
