Help, engine overheating

[pandos]

After putting up with a an annoying diesil leak for over a year, I bit the bullet today and took off the injector pump and fixed the leak. When I got the thing back together it ran Perfectly with no leak.

BUT:::::It is running very hot and the cooling water does not seem to be circulating.

There is plenty of water comming out of the exhaust, ( I fitted a new impeller)

I am pretty sure that I have all the cooling pipes back as before. ( I only removed those going to the calorifier and they are cut so that they only fit back on the same way)

I am bemused, it seems that the operation was a sucess but the patient may have developed complications????


Any suggestions. I motored for a few days last week and no bother, Motored this morning before the operation and boat at normal temperature. No sign of water in oil.?????

I am guessing air lock somewhere but how to sort this, Never had this problem in past and have had pump off before.

The engine is a md21b volvo penta.

 

[colinmi]

Yep

Sounds like and air lock. Can be a pain to sort out, but try the following.

Take the cap off the heat exchanger and run the engne for a few minutes. If this has worked, you will need to top up the exchanger as the air come out.

Slacken the drain down points on the block and manifold and anywhere else you have them and run the engine for a few minutes, topping up as required.

My engines are prone to the same problem when drained down(Ford Lehmans). This usually works well.

Good luck

Colin

 

[savageseadog]

You can eleminate airlocks with a lemonade bottle full of water just apply and squeeze to pressurise. Be careful not to backfill the exhaust system.

 

[orizaba]

one thing that can help prevent air locks is to drill a hole 3mm or slightly smaller in your thermostat this stops air being trapped below it,but does not affect its efficiency.
from what i have come across most of the air locks seem to be around the calorifier and would suggest slackening pipes to and from them to make sure there is no air trapped therespecially if the top of the cal is nr the top of the engine,
also giving the rubber pipes a sqeeze can sometimes shift an airlock..
if you have to take pipes of in future it may be an idea to back flush with a hose the system and calorifier as it amazing how much crud can accumulate

 

[pandos]

Thanks for the replies. It was an airlock that had rectified itself when I got the boat the following morning.

Tony.