cam chain tensioner

[BA BUSA]

???

Can someone correct me if I am wrong on this, but to my understanding the thermostat serves to restrict coolant flow to make sure the engine operates in a normal range, and opens up at a set temperature to allow full flow. So if there was no thermostat, the engine should run cooler, not hotter than otherwise?

and as to the OP problem please keep us informed

Most engines will overheat without a thermostat, because the coolant circulates too fast and is not in the radiator long enough to dissipate enough heat.
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[wardie]

actually I have observed the opposite. Take the thermostat out of your car's engine during the winter (here in Ohio). After 10 minutes let me know if you have any heat when you turn the blower on? Wardie

 

[psdiesel911]

alright we have the thing back together and its still making the noise and now its definitely in the cam chain area... we are thinking the tensioner might not be getting enough oil pressure due to a clogged line or something so we are picking up a manuel tensioner tomorrow and throwing that thing in there and hopefully that will fix it... we probably should have just done that in the first place instead of taking the head off but at least we know its all good in there.

 

[psdiesel911]

here is a few pictures of the tear down

 

[psdiesel911]

we put in the manual tensioner and a thermostat and nothing has changed it still makes the noise and it still overheats. The noise is defintely coming from the cam chain. Has anyone ever had their cam chain stretch?

 

[wardie]

I would find out if the water pump impellers are in good shape. Maybe they are worn down and the pump isn't delivering the GPH it should? Just a thought. I would also check coolant passages in the block. Wardie

 

[psdiesel911]

alright sounds good thats the only thing it could be because we went through that whole thing :/ thanks wardie
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[wardie]

check the hoses if they are soft change them. I've seen where hoses can collapse under pressure and restrict flow causing overheating. With the fairing on you wouldn't notice it. Just a thought. Good luck it's a bugger trying to find it but when you do it will so satisfing! Wardie

 

[GPW]

Did you check for valve wobble (play) ?? Sounds like a valve train issue. Have seen a 19K 26k and 48K Busa with a similiar problem. Also do a vacum check to ensure the valves are seating properly. Also check cam run out. Just some thoughts.

 

[psdiesel911]

well i know my dad checked the clearances and relapped the valves while i was in alabama for surgery a week ago or so... everything in the head seems to be in great shape. I just got the water pump off and it seems to be in perfect shape. The hoses are not soft and i rode it tonight for a good while just cruising and it did fine because its nice and cool out as opposed to earlier today when it was in the 90's. Also my temp gauge doesnt go over halfway even when its so hot it turns my legs red... Well i guess my plans for going to Maryland in the morning are scrubbed

 

[psdiesel911]

I just noticed the area code on your phone number GPW. I grew up in Bowie MD, PG county... thats where i was supposed to go haha

 

[ks-waterbug]

Five plus years without using a thermostat on my Big bore never had a problem with it overheating....

 

[psdiesel911]

Even though a streched chain never happens, if it was streched ever so slightly could that litle bit of timing change cause overheating and chain noise? There are no wear marks at all on cam gears though.

 

[mcbusaturbo]

compression was around 150??? I was trying to remember but I thought the service limit was 172 maybe I will have to look in my book again. but definitely sounds like you should have done a leak down to see where the majority of compression loss is coming from

 

[Mellow77]

psdiesel, could you feel a little clunk in your left foot peg under load? I have that and I'm not sure what it is just yet. It only appears to do it under load and the higher the rev the faster the clunk proportionately.

 

[psdiesel911]

no i cant feel any thing abnormal just the noise but your water pump is right there at your left foot
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