Perkins M30 coolant loss

[Tamar]

Hi
My Perkins is running well with about 2000hrs on the clock. For the last few months it has been intermittently dumping coolant into the bilge.
There seems to be a lot of pressure in the system.

I put a bottle on the end of the overflow pipe to catch the excess, it's around 300ml after around 3 hrs motoring.

I just put it back in next time, however the last few days the temp gauge after about 5 minutes running moves up to around 200f and almost straight away back to normal.

Today after around 4 hours motoring the temp went again to 200f and stayed there until I managed to pick up a bouy. I let it cool down and topped it back up and it was fine until we got back to our berth.

I had the head gasket changed last year and the valves lapped in so hopefully not that.

Could it be a faulty thermostat?

I bought new rubber end caps for the HE a few months ago because I thought it might be them causing the problem, but I haven't had chance to change them yet. I have also changed the radiator cap.

Thanks in advance for any advice.

 

[Boater Sam]

If the cooling system is pressurising more or faster than usual then it does suggest the head gasket is failing.
You can buy a kit which will check the coolant for products of combustion contamination.
A faulty stat will cause overheating but not water to be ejected unless you are overfilling in the first place.

 

[Tamar]

If the cooling system is pressurising more or faster than usual then it does suggest the head gasket is failing.
You can buy a kit which will check the coolant for products of combustion contamination.
A faulty stat will cause overheating but not water to be ejected unless you are overfilling in the first place.

Thanks. It's intermittent which is more annoying, it will be fine for a week then start ejecting fluid

 

[ridgy]

We have an M20 in our Greek share boat which had an identical problem last year and it was the head gasket. The gasket was only about 6 years old.

 

[Tamar]

We have an M20 in our Greek share boat which had an identical problem last year and it was the head gasket. The gasket was only about 6 years old.

Yes I agree. Head gasket ordered.

 

[Ammonite]

I don't know when the change was made but the MD20X0 series now use stretch bolts for the head...so worth getting a set of these if fitting a new head gasket https://parts4engines.com/products/...der-head-bolt-set?_pos=1&_sid=0f5b9f8e8&_ss=r
Ignore the torque specs in the workshop manual and use the figures that come with the bolts.

 

[Tamar]

I don't know when the change was made but the MD20X0 series now use stretch bolts for the head...so worth getting a setting of these if fitting a new head gasket https://parts4engines.com/products/...der-head-bolt-set?_pos=1&_sid=0f5b9f8e8&_ss=r
Ignore the torque specs in the workshop manual and use the figures that come with the bolts.

My engine is a Perkins M30/2030, does this apply to this engine?

 

[Ammonite]

My engine is a Perkins M30/2030, does this apply to this engine?

I'm pretty sure it will. If you give Parts4engines a shout and ask them to check the box it should have the torque specs inside. The bolts for my MD2040 were from Perkins.

 

[Tamar]

I'm pretty sure it will. If you give Parts4engines a shout and ask them to check the box it should have the torque specs inside. The bolts for my MD2040 were from Perkins.

I didn't know this... Perhaps it explains why I'm replacing the HG a year after I fitted the last one. I re used the old bolts

 

[Ammonite]

I didn't know this... Perhaps it explains why I'm replacing the HG a year after I fitted the last one. I re used the old bolts

In theory you should be able to re-use the original non-stretch bolts a few times (assuming they were the originals), although out of interest I used my torque wrench when doing the "plus x degrees" with the new stretch bolts and it was considerably higher the originals. I'm not sure if they have just moved with the times or were addressing an issue.

 

[Ammonite]

It looks like Parts4engines are out of stock of head bolts for the M30 and other engines that share the same bolts, so may not be able to confirm whether the M30 switched to stretch bolts. When I bought the set for my MD2040 the only indication they were torque to yield was a print out in the box. If you get stuck I'm pretty sure the Perkins part number for the bolt set for these engines is T436734 and these guys appear to have them in stock (ignore the image). They should hopefully be able to double check the part numbers and specs if you give them your engine serial number, and confirm whether yours has also been switched to TTY. Either way it would be a good idea to fit a new set and they are not expensive.
https://diperk.perkins.com/product/t436734/01t6M00000KWWXxQAP

 

[Tamar]

It looks like Parts4engines are out of stock of head bolts for the M30 and other engines that share the same bolts, so may not be able to confirm whether the M30 switched to stretch bolts. When I bought the set for my MD2040 the only indication they were torque to yield was a print out in the box. If you get stuck I'm pretty sure the Perkins part number for the bolt set for these engines is T436734 and these guys appear to have them in stock (ignore the image). They should hopefully be able to double check the part numbers and specs if you give them your engine serial number, and confirm whether yours has also been switched to TTY. Either way it would be a good idea to fit a new set and they are not expensive.
https://diperk.perkins.com/product/t436734/01t6M00000KWWXxQAP

Thanks

 

[peteK]

Hi
My Perkins is running well with about 2000hrs on the clock. For the last few months it has been intermittently dumping coolant into the bilge.
There seems to be a lot of pressure in the system.

I put a bottle on the end of the overflow pipe to catch the excess, it's around 300ml after around 3 hrs motoring.

I just put it back in next time, however the last few days the temp gauge after about 5 minutes running moves up to around 200f and almost straight away back to normal.

Today after around 4 hours motoring the temp went again to 200f and stayed there until I managed to pick up a bouy. I let it cool down and topped it back up and it was fine until we got back to our berth.

I had the head gasket changed last year and the valves lapped in so hopefully not that.

Could it be a faulty thermostat?

I bought new rubber end caps for the HE a few months ago because I thought it might be them causing the problem, but I haven't had chance to change them yet. I have also changed the radiator cap.

Thanks in advance for any advice.

Hi
My Perkins is running well with about 2000hrs on the clock. For the last few months it has been intermittently dumping coolant into the bilge.
There seems to be a lot of pressure in the system.

I put a bottle on the end of the overflow pipe to catch the excess, it's around 300ml after around 3 hrs motoring.

I just put it back in next time, however the last few days the temp gauge after about 5 minutes running moves up to around 200f and almost straight away back to normal.

Today after around 4 hours motoring the temp went again to 200f and stayed there until I managed to pick up a bouy. I let it cool down and topped it back up and it was fine until we got back to our berth.

I had the head gasket changed last year and the valves lapped in so hopefully not that.

Could it be a faulty thermostat?

I bought new rubber end caps for the HE a few months ago because I thought it might be them causing the problem, but I haven't had chance to change them yet. I have also changed the radiator cap.

Thanks in advance for any advice.

A restricted raw water flow through the spigot on the exhaust elbow can cause this problem,if the rubber end cap is hard thats a sign its partially blocked.This forces water in to the heat exchanger via the end cap thus causing the overflow.Its happened to me on a M20.
B

 

[Ammonite]

Returning to the original problem, if the end caps have been compromised due to a blocked injection point on the exhaust elbow this normally leads to coolant being lost via the exhaust, once up to temperature, rather than the cap in my experience, although the engine will eventually overheat and dump the remainder in the bilge. However, any significant restriction in raw water flow, even if the caps are still intact, will cause the engine to run hot when worked hard which could explain the intermittent nature of the fault. It could also cause the head gasket to fail. I think your best bet is to start with test kit mentioned earlier and then work you way through the rest of the raw water system as the last thing you want is to replace the HG and find it was a symptom rather than the cause.

 

[Tamar]

Hi all, thanks for the advice. This morning I decided to tighten the head bolts to see if they would make a difference, they were no where near the 70nm they should have been. Started the Engine and straight away it sounded different. An hour's motoring some at full speed and no coolant has been expelled and at the end of the test I took the cap off and hardly any pressure in the HE. Hopefully fingers crossed I have fixed it.

 

[Ammonite]

Are you sure thats the correct torque as the MD2030 is only 50 - 53 Nm (I don't have the M30 manual). If it is correct make sure you check the tappet clearance if you haven't already.

 

[Tamar]

Are you sure thats the correct torque as the MD2030 is only 50 - 53 Nm (I don't have the M30 manual). If it is correct make sure you check the tappet clearance if you haven't already.

The book says 20Nm first pass, 70Nm second pass, then 90deg to finish.
Good point about the tappets, my job for tomorrow.

Edit
You are correct.
I was reading the wrong engine, thanks for querying