Volvo Penta MD2 Advice

[onemanandhiswesterly]

Hi All,

I have bought a Westerly Renown as a project and am in the process of getting the engine up and running.

After much cranking with the poor starter motor I finally got it started last weekend. The first time it only fired while the starter motor was running then cut out. The second time I managed to get it to fire and run using a couple of squirts of diesel into the air intake and it ran continuously after that.

I am new to working on diesel engines but my theory is that the lift pump is not working properly so I am not getting enough fuel to the injectors until the engine is actually running at decent revs. I have heard that there is a diaphragm in there which may have perished.

I have checked the supply line to the injectors and this drips diesel while the engine is turning over so it's a bit confusing.

Is it worth looking at the fuel pump and does anyone know where I might get the parts to repair it?

Thanks in advance!

 

[VicS]

Hi All,

I have bought a Westerly Renown as a project and am in the process of getting the engine up and running.

After much cranking with the poor starter motor I finally got it started last weekend. The first time it only fired while the starter motor was running then cut out. The second time I managed to get it to fire and run using a couple of squirts of diesel into the air intake and it ran continuously after that.

I am new to working on diesel engines but my theory is that the lift pump is not working properly so I am not getting enough fuel to the injectors until the engine is actually running at decent revs. I have heard that there is a diaphragm in there which may have perished.

I have checked the supply line to the injectors and this drips diesel while the engine is turning over so it's a bit confusing.

Is it worth looking at the fuel pump and does anyone know where I might get the parts to repair it?

Thanks in advance!

Are you sure its an MD2, not an MD2B. ITYWF that production of the MD2 ceased well before the Renown was first produced

You can check the operation ofthe pump by disconnecting the feed to the filter and operating the hand priming lever ( but you may have to turn the engine so that the cam follower is not on the toe of the cam).

The original pumps are obsolete and AFAIK there are no spares available . Replacement sealed pumps are available. https://www.keypart.com/stock/21134777-r

 

[Kurrawong_Kid]

Two things come to mind. If your MD2 only has a Dynastart, they do not spin the engine very fast. You may find that if you get someone to push the starter button whilst you turn the crank as fast as you can that it will fire up without easystar and run OK. Get a good speed up before having your assistant lowering the decompression levers! Secondly check that the cold start button is down before and at each attempt at starting. The little filter in the lift pump may be blocked but since the engine runs OK when started I would not go chasing that first. If starting continues to be difficult you may need to have a compression test to see if the rings are worn.

 

[Kurrawong_Kid]

Are you sure its an MD2, not an MD2B. ITYWF that production of the MD2 ceased well before the Renown was first produced

You can check the operation ofthe pump by disconnecting the feed to the filter and operating the hand priming lever ( but you may have to turn the engine so that the cam follower is not on the toe of the cam).

The original pumps are obsolete and AFAIK there are no spares available . Replacement sealed pumps are available. https://www.keypart.com/stock/21134777-r

Part 834255 From Keypadt is a service kit for the obsolete pump.

 

[onemanandhiswesterly]

Are you sure its an MD2, not an MD2B. ITYWF that production of the MD2 ceased well before the Renown was first produced

You can check the operation ofthe pump by disconnecting the feed to the filter and operating the hand priming lever ( but you may have to turn the engine so that the cam follower is not on the toe of the cam).

The original pumps are obsolete and AFAIK there are no spares available . Replacement sealed pumps are available. https://www.keypart.com/stock/21134777-r

Thanks for the information. Yes you are right it's an MD2B not an MD2.

I'll try what you suggested. Given that the fuel is dripping out of the inlet pipes to the injectors suggests to me that the lift pump must be working to some extent. I'm not sure what to expect in terms of flow rate though.

 

[onemanandhiswesterly]

Two things come to mind. If your MD2 only has a Dynastart, they do not spin the engine very fast. You may find that if you get someone to push the starter button whilst you turn the crank as fast as you can that it will fire up without easystar and run OK. Get a good speed up before having your assistant lowering the decompression levers! Secondly check that the cold start button is down before and at each attempt at starting. The little filter in the lift pump may be blocked but since the engine runs OK when started I would not go chasing that first. If starting continues to be difficult you may need to have a compression test to see if the rings are worn.

I think it's a starter motor rather than a dynastart but good idea about assisting with the hand crank.

One thing I didn't mention is that the cold start button does not stay depressed so I have been attempting to start without it. Could this be connected to the issue or am I using the cold start incorrectly?

In terms of compression I had one of the guys at the yard check the compression by hand cranking the engine with the compression levers up and down and he thought the compression felt ok. Not sure if I can read anything into that or not?

Thanks!

 

[onemanandhiswesterly]

Part 834255 From Keypadt is a service kit for the obsolete pump.

Thanks. Cheaper than replacing the whole pump. Still surprisingly expensive.

 

[Vegable]

"One thing I didn't mention is that the cold start button does not stay depressed so I have been attempting to start without it. Could this be connected to the issue or am I using the cold start incorectly"

I had a Renown with the MD2B engine but took it out 18 years ago. With the Renown you can take up the cockpit floor and see right into the engine bay AND the throttle control and cold start wires whilst moving the throttle control. I remember that a throttle movement moved a cam that hit the cold start button and released it. As it was nearly 20 years ago I can't remember where the throttle position was/is when that happened. If you operate the throttle with the floor removed you'll see the bit I'm referring to and you'll be able to spot what's happening. I think you may be openning the throttle too much to start the engine.....but not sure enough to state with certainty!
Mike

 

[VicS]

I think it's a starter motor rather than a dynastart but good idea about assisting with the hand crank.

One thing I didn't mention is that the cold start button does not stay depressed so I have been attempting to start without it. Could this be connected to the issue or am I using the cold start incorrectly?

In terms of compression I had one of the guys at the yard check the compression by hand cranking the engine with the compression levers up and down and he thought the compression felt ok. Not sure if I can read anything into that or not?

Thanks!

The button must stay depressed in order to be effective . It should latch down but the latch wears so that eventually it does not stay down. There is, I believe, a fix for this for anyone bold enough to go there. IIRC it just involves turning a component round so that an unworn part replaces the worn part.

It is however a device for starting the engine in cold weather rather than a device for starting a cold engine. but we always used it if the engine was cold ... at least we depressed the button but I have an idea that the owners technique for starting the engine probably released it again prematurely

I am nor certain quite what releases the button.

 

[beef]

Haven't tried it myself but this might be worth a go..

https://m.youtube.com/watch?v=PGMUGjlV5HU

 

[ghostlymoron]

Not sure if you're doing this but operate the decompressors whilst turning on the starter until up to speed, then drop them. The engine will then be spinning much faster and more likely to start. Also is the battery in good nick? This could affect cranking speed.
If the cold start button doesn't stay down starting is much more difficult. It needs fixing but I've no idea how.

 

[onemanandhiswesterly]

Not sure if you're doing this but operate the decompressors whilst turning on the starter until up to speed, then drop them. The engine will then be spinning much faster and more likely to start. Also is the battery in good nick? This could affect cranking speed.
If the cold start button doesn't stay down starting is much more difficult. It needs fixing but I've no idea how.

Thanks for the reply. I've been starting the engine with the levers up then putting one when the fly wheel is up to speed. I'm using a brand new starter pack so should be ok.

The cold start button not staying down is a bit of a mystery. I'm going to take the lift pump apart first and maybe getting that sorted might mean I don't need the cold start for now.

 

[neil_s]

It's still quite cool out - old diesels are often reluctant to start in the spring - my Bukh certainly is. Especially if the motor hasn't been used for a while, compression is a bit low until the valves bed in and the oil circulates. I wouldn't get too worked up about reluctant starting until the engine has had a good run at full throttle. The fuel dripping from the injector pipes, though. Was that because you had slackened off the unions to check or is it happening all the time? If so that needs to be fixed.

 

[Bilgediver]

The cold start button will only latch down if you have advanced the speed lever sufficiently. Put the throttle past the click position.

To start a reluctant MD2b DO NOT USE EASYSTART ... This contains ether and ignites the mixture prematurely creating excessive cylinder pressures which can promote leaking head seals and other problems.

A much better method in cold weather is to remove both air filters and using a squirt type oil gun squirt about 5 squirts of engine oil into each inlet space. Wind the engine at least two turns by hand decompressed to spread the oil around valves and pistons.Replace the filters and start. You should not need to repeat this process on subsequent starts unless the rings and or valve seats need attention. The heads are easily removed for maintenance and the pistons can be exposed by lifting the individual blocks. Usually no need to remove the engine.

I also inject oil as above as part of winterising.

 

[Kurrawong_Kid]

The cold start button will only latch down if you have advanced the speed lever sufficiently. Put the throttle past the click position.

To start a reluctant MD2b DO NOT USE EASYSTART ... This contains ether and ignites the mixture prematurely creating excessive cylinder pressures which can promote leaking head seals and other problems.

A much better method in cold weather is to remove both air filters and using a squirt type oil gun squirt about 5 squirts of engine oil into each inlet space. Wind the engine at least two turns by hand decompressed to spread the oil around valves and pistons.Replace the filters and start. You should not need to repeat this process on subsequent starts unless the rings and or valve seats need attention. The heads are easily removed for maintenance and the pistons can be exposed by lifting the individual blocks. Usually no need to remove the engine.

I also inject oil as above as part of winterising.

+1. When I had a MD2B I always used the cold start button when the engine was cold whatever the weather. If there is not wear in the cylinders they are solid reliable engines which start relatively easily but benefit greatly from the nearest you can now get to the correct oil changed very regularly to prevent cylinder bore wear. 20-50 mineral oil CC was originally specified but nowadays you may have to settle for 15-40 mineral oil at CF.