When i got the van the cylinder head temp used to sit at 350 farenheight plus degrees give or take, eventually i did the timing and it sat at 270ish (when it worked) meaning sometimes it sits at zero for ages and sometimes when you start the van it shoots off the scale..... so it may be faulty? now i've just driven the van to work and it's sitting at 360ish and i've touched nothing! all i've done that MAY affect it is fit heat exchangers and pipework etc, but all i did that could change summat is on the end of the fan casing (type 4) when you fit j tubes you cap the fan end off, all i did was remove the caps and marry the exchanger up to the fan output, it's possible the gauge is faulty but last time i drove the van it was ok. Any ideas? i'm wondering if the fan is now not pushing as much air round the engine and instead now pushing it to the cab?
nobody? i can't belive i haven't even got a sarcy answer, come on it's me rick, you know, everyones stooge.
honestly no idea mate, i guess what i'm asking is for a bit of a brainstorm, the gauge has always been intermittent but has unblocking the fan ends and putting exchangers on instead of j tubes caused a heat increase or is it coincidence, as with any worry gauge sometimes if you didn't have it you wouldn't care, van seems to run ok exhaust sounds different that's all.
Think I'd go for the thermocouple making poor contact with the head first. A slightly cruddy contact surface is going to mess up heat transfer.
Rick This all depends on where the thermmocouple is sited. The thermostat ona Type 4 engine starts to open at 90deg C (194deg F). Remember that it is sensing the AIR flowing around under the left hand cyclinders, not the oil temp or the metal temp. So if the temp of the air is minimum 194F and the max is what? maybe 230? But if your thermocouple is closer to the metal, or touching the metal of nearer to a hotter bit it will show higher. The only accurate temp reading is from an oil temp guage. I use the old test. Run the engine under load (ie drive it) for at least 30 mins. Can you hold onto the dipstick without burning your fingers? If you can you are all right. Found this on type2.com. 180 F: too cool; is the thermostat still there? 180-210: peachy. 210-250: can live with it; many busses w/ type4 engines get that hot under load in the summer. 250-280: something is wrong and must be fixed; however, viscosity of good synthetic oil should still be fine. If it's after dark and I'm in East St. Louis, I keep on driving. 280 F: better stop; unless the oil pressure light is on (in which case you must shut the engine off immediately!), let the engine run. Glen Buhlman recommends that it not be left idling, but that revving it will allow the fan to do a better job of cooling the engine.
no oil temp on mine, although when i got to work engine bay was cool enough and dipstick wasn't hot, fair bit of heat under the van though and decent heat in the cab (complete with oil smell lol)
no thermostat on my van by the way (yeah yeah i know) but it's never been on since i had it, and as i say the temp has read ok recently, true exchangers have 'closed up' the area under the van a bit (no bottom tin either - again yeah yeah i know) i'll feel the dipstick later and see how hot it is
Head temps,,gauge is prob. conected to numb. 3 cyl. should never get pass the 350 f mark. Is your timing still good ?
hi jan yeah as i say saturday morning before fitting exchangers sat at 270 all ok, put on ramps changed from j tubes to exchangers and drove today reading 360 no area of timing touched so the only thing changed is fitting of exchangers and uncapping of fan outputs plus obviously making the bottom of the engine more 'cluttered'
when you run j tubes you block the fan outputs on a type 4 where they connect to the exchangers, obviously when you fit exchangers back on you un cap the fan so it can push the air over the exchanger to the cab.
You have less air being used from the fan to cool the actual engine now as part of it is blowing over the heat exhchangers to warm the bus Temp block the fan outputs again and i bet the temp drops back down
ok guys cheers - para that's basically what i'm thinking, i'll get the plugs out at weekend and also see what the fan does if i run the engine faster (leave in 2nd to spin it faster)
right, little update just drove home from work and tried a few things, if you use temp gauge as a guide and ignore the numbers it does obviously do someting, normal driving on flat no load sits at 350 drop it down a gear and thrash it it drops down to 300 go uphill labouring it goes up go uphill thrashing it goes down, so this confirms my thought and what para said that the fan is now not cooling as much due to it pushing hot air into the cab, (which is lovely and warm even without snail fan fitted and any pipes under van lagged yet plus a few poor joins) anyway, when i got home i pulled the dipstick out and although it's warm i was able to grab it in my hand and hold it easily without it being too hot, i'm presuming then that although it's running hotter than it was before i fitted exchangers it still is cool enough to not do any damage and the temp gauge is probably not 100% reliable, i'm gonna investigate the connections as advised but i'm thinking i shouldn't worry too much at the moment based on the fact that the oil isn't hot, maybe it's not a bad thing i've got no thermostat at the moment.
