Hey All,

so When I was driving my van down to start the rebuild it was like 44 degree's. When I was going up a big hill the temp gauge went from normal temp to HOT HOT HOT in about 10 seconds. Steam and bioling occurred. Does this sound like a head gasket, thermostat
or something really bad like a water jacket bursting or something I can't even imagine?

Any thoughts people?

I am nearing putting my motor back in and it has not run since this. ( not as in doesn't run but as in its been out of the car wrapped in rags)

check all your hoses and check for leaking coolant - you could be losing water. if you arent losing power and you aint puffing gusts of white smoke out the exhaust then i doubt youve dont the head gasket. check under the rocker cover for oily water to double check. check thermostat by taking it out and putting it in boiling water to see if it opens. check your timing too, can cause overheating issues

so it boiled BEFORE you took it out of the car, and now you're asking just to make sure there's nothing likely to be wrong, yeah?

when you put it back in, make sure everything is in perfect condition - do the head gasket, new thermostat, flush the block, new water pump, radiator professionally cleaned out, tuned & timing right etc. etc. etc. etc.

_________________
did I tell you that I won a trophy?

Timing Is very important In my opinion the most over looked reason for overheating

Yeah thats right. As mentioned before it happened on a 40 odd degree day back in april and I think that is the main reason for the over heating. Just checking what people think might be the problem if not so I can check while the motor is out and easy to get to.

I have had the rad flushed out and cleaned by a rad place. I will order a new thermostat and hoses anyway as it seems like good sense. Do you guys run the 74 degree, 84 degree or something else I don't even know about. I read ( when searching on this subject ) that some people have a summer and winter thermostat and change them. Do you guys do that?

I really didn't want to do the head gasket as I was afraid I would just stuff it up to be honest. It seems like these are prone to stuff up if not done perfectly and mine SEEMS to be fine so what do you all think? I guess it comes down to that old thing of where do you stop on a rebuild.

Thanks again fella's

D

I'm with John I think your Timming is Out

But Change what you are changing. I use a 74% Thermostar Year round but clean the system regulary, but I do need to do a oil change

Head Gasket..does it sound like a VW
or do the Bushies Compression Test, run the engine without a spark plug in each of the hole with your thumb over the top of it.
They Should all feel the same

_________________
Stop Licking the Dog...I Don't Care Who Started It

a hot day isn't a reason for overheating - it may be a catalyst, but it's not a reason...

I drive my cooper s every day no matter how hot it gets, and it's never over 2/3rds of the way up the gauge when sitting at the lights etc. then as soon as I get moving, it drops down to well below half

I sat it idling one day and let it heat up and used a remote infra red thermometer thingy and measured the temperature all over the motor and nothing was over 80 degrees (extractors are at 242 degrees C!)

my engine is a bit gruntier than standard, and I've got a completely stock cooling system



honestly, there are too many reasons for overheating to list - and any number of them could be the cause - so I go back to what I said, make everything perfect - they didn't overheat from the factory, it's only years of neglect that get them into that state



it is good sense - but get a new water pump too, and flush the block out with water.

Block up the heater outlet, remove the thermostat, put the thermostat housing back on and clamp a high pressure garden hose nozzle into the top radiator hose. Turn on the tap and let water blast through the motor until clean water is coming out of the bottom radiator hose, then clamp the garden hose into the bottom radiator hose, and do the same thing - keep doing it until the water runs out clean both ways...

take the heater out of your car and do the same thing, if it's a clubby one, it's a 5 minute job to remove the heater core and give it a good shake to loosen up any junk and get it out of there



I've never needed to run anything other than an 82 degree thermostat, but a hotter (90?) one in winter might be a good idea because my car does run too cold at times



follow the workshop manual and it's pretty hard to make a mistake - most important bit after properly torquing the studs is that the mating surfaces (head, block, manifold) must be utterly spotless - to the point where you can wipe them with a tissue and it comes off clean

if you stuff it up, then you do it again, and you don't make the same mistake - simple

_________________
did I tell you that I won a trophy?

It is usually always fine but was only bad on this one day though ( that was really hot). Still timing?
Guess I cant check timing till its back in the car and running though.

check cooling system has pressure , before engine boils (that rad, pressure douse the cooling ) could be faulty , rad cap, lot of faulty new ones about took 3 before i got a good one , ign, could be to retarded ? :?

well I boiled my thermostat on the stove and used my girlfriends dad's laser thermometer thing. That is a fancy bit of kit. I want one. Not sure what I would use it for but since when has that mattered.

at approx 85 degree's it opened up so it seems to be working well. I am gonna get a new one as its a bit rusty and thought it would be worth it. Might get the 72 degree one to get it to open earlier.
will keep looking and see what else it could be. Have had rad flushed and will flush out the motor whilst its out.

took photo's but will load later.

If you have the engine out and you want to be sure it's clean - knock out the welsh plugs and poke, scrape, chisel, suck, blow and generally clean out the water jacket - you'll be surprised how much crud will be in there - especially the clutch end. I got a heap of casting sand still in there as well as some left over support wire

_________________
David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!