Thermostat Housing

[Guest pitty]

Hello been a while new pump and fuel tank fitted has been running well . However its decided to overheat and i am pretty sure its the thermostat stuck shut . fitted new temp sender and its running warm . so my question is one of the bolts for the thermostat housing the top one by the dizzy has broke what is the best way to sort this ? any ideas

 

Cheers

[Himanshu]

1st option is to use left handed drill to try and drill it out, or ez out, however this is a hit and miss approach, the other thing is too take the cylinder head off, take it to an engineering shop to try and drill it out and re tap it or else helicoil it. If you are taking the cylinder head off, you can decard the head, port it gas flow it, and lap in the valves, if the head is not designed for unleaded. you can inspect the bores. If they are worn, you need just to take the sump of, and take the pistons out and put over size rings, and re hone the walls, providing the measurements leet you. If you don't fancy that, just drill it out, and use a drill and tap to go up a fastener. The head is ally and reasonably easy to tap providing you ge the position of the bolt stuck in out. I have done the same myself, and I just took the head off, a 2 hour job, changed the timing belt, decarbed the head, took the sump off, re ringed it, got a locale engineering shop to skim and place new valve guides and hardened valve seats inside it. Whilst there I replaced the camshaft , camshaft seal, this ended up costing me £500. But the Engine covered another 100K and ran sweet as! If you do decide on the cheaper fix, of drilling out, get Loctite Shock unlock and spray into the fastener. I some times having followed the instruction on this, and run a left handed drill the fastener has come out, without any damage to the threads.

[gingergman]

If enough thread is sticking out put two small nuts on it, do them up then lock them together, then undo the first nut and it will wind the bolt out.