question Roll Royce B81 engine - coolant loss when exhaust manifold stud removed

[djwalker]

Today I started to remove the exhaust manifold from the B81 engine of my stalwart. The first stud to come out was followed by a flow of engine coolant. The manifold was still very firmly held against the engine, with 14 or 15 more studs still in place, so I think the coolant was flowing from out through the hole in the engine from which the stud was removed rather than out of the manifold itself and down the crack between the engine and into the hole. But I might be wrong....Anyone know enough about this engine to know if the studs hold coolant back?

 

In short I am asking does anyone know if some/all of the exhaust manifold studs on this engine protrude into the water jacket?

Edited April 28, 2013 by djwalker

[Richard Farrant]

In short I am asking does anyone know if some/all of the exhaust manifold studs on this engine protrude into the water jacket?

 

The exhaust stud holes do run through to the water jacket.

 

regards, Richard

[snort]

I had this with a Ferret once, it poured out. Sorry to say that I used K-seal in the system as I wanted to use it straight away. ...........................and it was still in there a year later!

[djwalker]

Richard - you have made me a happy man. I am so endebted to you for this info, and so quickly provided too. I have perhaps not read the unit repairs properly but so far I found now mention of expecting that. Perhaps the coolant loss is small. Would you advise that I drain the entire system (12-14 gallons I seem to recal)? Sincerely, Dan W

 

The exhaust stud holes do run through to the water jacket.

 

regards, Richard

[Richard Farrant]

Richard - you have made me a happy man. I am so endebted to you for this info, and so quickly provided too. I have perhaps not read the unit repairs properly but so far I found now mention of expecting that. Perhaps the coolant loss is small. Would you advise that I drain the entire system (12-14 gallons I seem to recal)? Sincerely, Dan W

 

Hi Dan,

You will have to drain it to below the manifold level, but no need to drain all of it out.

[djwalker]

Absolutely, Richard - will do. I have just returned with my son and daughter from stal54. We have started her on the starting handle. What another relief! I sat in the cab, ignition on, and engaged starter switch in the belief that that by-passes the ballast resistors and gives the full ~24v to the ignition coil. James (16 but big and strong) on starting handle. Karina (14) in load bay with a syringe (minus hypodermic needle of course) with 1ml neat di-ethyl ether. I give the signal, she injects ether in a blast, engine fires immediately! Within 180 rotation James said.

 

Am going to get her under cover later this week. That will mean driving ~40miles with exhaust manifold held on with only 15 of the 16 studs. Planning to improvise a heat shield (any suggestion?), having bagged nasty corroded and by the look of it asbestos filled one.

 

Best wishes, Dan

 

 

Hi Dan,

You will have to drain it to below the manifold level, but no need to drain all of it out.

[Richard Farrant]

Absolutely, Richard - will do. I have just returned with my son and daughter from stal54. We have started her on the starting handle. What another relief! I sat in the cab, ignition on, and engaged starter switch in the belief that that by-passes the ballast resistors and gives the full ~24v to the ignition coil. James (16 but big and strong) on starting handle. Karina (14) in load bay with a syringe (minus hypodermic needle of course) with 1ml neat di-ethyl ether. I give the signal, she injects ether in a blast, engine fires immediately! Within 180 rotation James said.

 

Am going to get her under cover later this week. That will mean driving ~40miles with exhaust manifold held on with only 15 of the 16 studs. Planning to improvise a heat shield (any suggestion?), having bagged nasty corroded and by the look of it asbestos filled one.

 

Best wishes, Dan

 

Hi Dan,

Sounds like you have a good team there, all co-ordinated !

As for heatshield there are some materials around now that you could use to form up a replacement, not used them myself.

The 24v to the coil is probably not needed when handcranking as it is there to compensate for power that the starter is drawing normally. But worth a try anyhow.

 

regards, Richard