Leyland truck / bus engine 680

Before going to all the effort of lifting the heads I would be looking for a better diagnosis of where the water might be coming from. For example pressure test each cylinder as well as the cooling system. The injector pump is lubricated by a bleed from the engine oil pump and it must be rare for oil to leak past the primer. It sounds like your motor may have sufferered some kind of abuse in a past life so knowing it's chequered history might be helpful in pointing the way with other problems.
The only way you will get a manual on cd is if someone dismantles a book and scans it page by page (curled soft edges won't feed into an auto scanner).
Power plus came in around 1961 so yours is the higher horse power, but it would help if you got the engine number as there were some detail changes along the way.

I have had the rear head off and did the gasket while it was off. It had a rattle and a bit of water in the cover, so I pulled the head off, replaced the gasket while it was off. There was no water or signs of from the front head so I left it alone (as I was on the road away from home) . I will be pulling the cover off tomorrow, and will see if that's the issues
As for the primer pump, the leak is coming from the seal in the bottom of pump, under the diaphragm and spring. There is a hole in the bottom to release oil should a leak occur to avoid contaminating the fuel. Obviously it has a leak! It is pouring out! I pulled the pump off and apart today and it has a very worn seal in the bottom. It is an Italian brand. I will take a pic and post tomorrow. Not sure where else to look for water leaking to oil. Hence the need for manual. Any help would be great.

If you found a bit of water under the tappet cover and no where else it is most likely due to condensation, which may occur with short runs and parking it outside. I wouldn't bother trying to repair the lift/primer pump as it will only give you further grief, just replace it.

Malcolm e-mailed me this photo.
DPA pump, layout etc is completely foreign to the vertical 680's I've had so my manual is no help.
I can't even see the compressor !!!!

Malcolm, those lift pumps are cheap at less than $50. A new one is cheap insurance because if the diaphragm leaks, it will dump fuel, at pressure, into the sump and you'll be spinning bearings before you even realize there is a problem.

If you found a bit of water under the tappet cover and no where else it is most likely due to condensation, which may occur with short runs and parking it outside. I wouldn't bother trying to repair the lift/primer pump as it will only give you further grief, just replace it.

Seen that before some condensation in a Leyland from sitting around.
Most buses never had power plus engines in them.

A couple of questions so that without pictures the set up can be imagined.
Does your injection pump and lift pump look like the picture Jeffo has posted? This shows a DPA pump which has the injector pipes coming out of the back of it and the lift pump in the drive housing in front of it.
Alternatively, you may have an 'in line' injection pump with the lift pump mounted on the side of it and the pipes coming out of the top.
The in line setup can leak fuel into the injection pump as well as through the tell-tale hole at the bottom near the diaphragm. This can end up in the engine sump depending on how the injection pump is supplied with lubricating oil. I have had a lot of trouble with both CAV and Simms lift pumps leaking during the last two or three years.
Is your water pump belt driven or gear driven? If it is gear driven directly from the engine it is possible for coolant water to leak into the engine and its oil if a seal in the water pump fails. This is a common fault on this type of coolant pump to which Gardner engines for example are particularly prone.

Malcolm e-mailed me this photo.
DPA pump, layout etc is completely foreign to the vertical 680's I've had so my manual is no help.
I can't even see the compressor !!!!

G'day GB this is a pic of Malcs eng


Jon

Export versions may have been different to UK versions so there are other possibilities. The engine may have an oil cooler fitted, in which case it is possible for the coolant to leak into the engine oil. YES it is.

There is a DPA style lift pump on ebay at the moment.

Assuming that the coolant being noticed in the oil is being seen on the dipstick and not merely in the mouth of the oil filler.

FYI for those looking, the compressor is mounted off the front (ie the very left of the photo)

How much water/coolant are you really using? how much condensation or cream are you finding?

Now talking half asleep here so I could be wrong, if it is a bad leak but you cant find an external cause im thinking you may have an injector tube issue (again its late and I could be mixing up motors)

Being a 76 model with electric change its a private unit probably ex Victorian one at a guess.

Love to see a pic when you get the chance