Heat, as in running hot.

[Canine]

Before I tear Lillibeth's head off I suppose I should check with the ol forums.

1. Recently on a trip to Neah bay my temp gauge shot up to 250 and stayed there. I confirmed it with my temp gun.

2. I've flushed the cooling system, thermostat is working fine, pump is new, 6 blade fan installed (sheesh that takes some tweaking), radiator is about a year old (super cool) I'm convinced the cooling system is doing all it can.

3. compression seems good in all cyl, the plug in the #1 cyl looked white, very hot looking. No foamy oil, no coolant loss.

Am I wrong in thinking this has to be a head gasket? It's just I've not seen a head gasket fail without other symptoms.

Any ideas?

Thanks, sorry I won't be in Portland I've got to tear a head off.

Cheers in advance though, have a tech session for me.

Greg

[Peter J Larsen]

I had the same on my Inno.
Check the temp sender unit, make sure the the reading heater instrument unit
is well grounded.
make sure, in case get the right temp sender for your car and instrument.

peter

[Canine]

I had the same on my Inno.
Check the temp sender unit, make sure the the reading heater instrument unit
is well grounded.
make sure, in case get the right temp sender for your car and instrument.

peter

Thank you Peter, as I said I checked the head temp with my thermal gun, and it was reading true, I think the temp is what it is, tonight I drove it and it was boiling, time for a head gasket I think.....

[Canine]

After head removal.

After removing the head I noticed the two inner cylinders were very carbonized, it was the most unusual thing I saw. It seems the gasket was leaking between the two center cylinders is this common?

I have a new set of ARP fasteners that look much stronger than stock. I love the hex inset in the ends that allow them to be inserted without munging up the threads, brilliant!

Any other suggestions for head installation? I will be using a composite gasket, not the copper one.

Thanks ahead of time

Greg

[Cheleker]

How do you know the thermostat is working correctly?

[Canine]

boiled parts..

How do you know the thermostat is working correctly?

Boiled it and it opened at the correct temp. also when I did my thermal scan everything was hot pre and post thermostat.

I am a bit confused as to where the thermostat should be though Chuck, mine is in the riser housing above the head which allows coolant to flow into the heater core (I took your advice and pressure checked the heater core and connections as well) I'm assuming this is where the thermostat needs to be and not down in the head.

Thanks for your help!

Greg

[mascher]

It's not common for a head gasket to fail on an A-series engine. When it happens it's common to see it between the center cylinders. It's almost impossible to get a good compression test with this fault.

There are a lot of mediocre head gaskets available. It's not a bad gasket because it has a piece of copper foil on it and not good because it's a composite non-copper type. What part number is on your new head gasket?

Head studs should not be tightened into the block. Finger-tight at the tightest, I usually back them off a quarter-turn. Some sealant on the threads can't hurt and helps to keep them from corroding in place.

The carbonized center cylinders and a lean #1 cylinder could mean you had a small vacuum leak on #1 and compensated by making the overall mixture rich. #4 often runs a bit hot so it can be hard to judge.

Kelley

[Canine]

Head Gasket.

The gasket was part of a Payen CF 473 kit. I've had temperature swings in the past but this was the first time it didn't come down, ( I had purchased the kit in anticipation of this repair). As usual I found other things that needed tending, carbon deposits cleaned off, exhaust nut that wasn't even finger tight, a chance to adjust the valves again etc.

Any idea what the torque spec is for an ARP head bolt?

Thanks for back off a quarter turn tip, I was going to seat those puppies,

Greg

[Cheleker]

The ARP bolts come with a torque spec. sheet and ARP lube.

Head studs, if using oil, 60 lb.ft.
Front stud on an 11-stud head, if using oil, 45 lb.ft.
Front 5/16" bolt on a 10-stud/one-bolt head, if using oil, 33 lb.ft.
Rocker studs, if using oil, 30 lb.ft.

Head studs, if using ARP lube, 40 lb.ft.
Front stud on an 11-stud head, if using ARP lube, 30 lb.ft.
Front 5/16" bolt on a 10-stud/one-bolt head, if using ARP lube, 22 lb.ft.
Rocker studs, if using ARP lube, 20 lb.ft.

Remember to clean the studs before installing to get the coating off of them.

"Screw studs into the block using 4 ft lbs only. (Basically hand tight)."

Check the rocker studs. If two are longer, they go on the outside.

I clean the threads in the holes and make sure there is no oil or water in them.

I also slightly chamfer the holes.

[Canine]

Head Studs

The ARP bolts come with a torque spec. sheet and ARP lube.

Head studs, if using oil, 60 lb.ft.
Front stud on an 11-stud head, if using oil, 45 lb.ft.
Front 5/16" bolt on a 10-stud/one-bolt head, if using oil, 33 lb.ft.
Rocker studs, if using oil, 30 lb.ft.

Head studs, if using ARP lube, 40 lb.ft.
Front stud on an 11-stud head, if using ARP lube, 30 lb.ft.
Front 5/16" bolt on a 10-stud/one-bolt head, if using ARP lube, 22 lb.ft.
Rocker studs, if using ARP lube, 20 lb.ft.

Remember to clean the studs before installing to get the coating off of them.

"Screw studs into the block using 4 ft lbs only. (Basically hand tight)."

Check the rocker studs. If two are longer, they go on the outside.

I clean the threads in the holes and make sure there is no oil or water in them.

I also slightly chamfer the holes.

Thank you Chuck! I did everything you said except I forgot to chamfer the holes they had stinky oil in them.

Fresh oil change, and new filter and Lil is a happy camper that isn't even getting hot on my hill climb home!

Thanks again for a successful job.

Greg

PS I have a lead on an original MkII cooper S that's in excellent shape. Any thoughts as the the value?