Perkins Prima 50 hp

[trackhappy]

"Hi Marc. Thanks for posting all that, it is very helpful for potential or current owners.
If the blue smoke goes away and it always does that, then I'd agree, do nothing. Robert though, has said that his is getting worse over a relatively short period, which I would be concerned about. I suspect his may be injectors or pump as well as the seemingly common blue smoke at startup. Maybe it is also a symptom of the timing belt being worn as well based on his mechanics comments on pump timing.

Wild personal theory time [img][/img] --- (The blue smoke at startup issue is very likely oil sitting around the valve guide(s) after shut down being drawn down into the inlet valve induction area as the engine cools. Off the top of my head, a fix may be to manufacture a small sleeve to light press fit over the top of the valve guide to raise its height above any pool of oil that may be sitting there.) ---

As you rightly suggest though, as a choice, I'd defintitely steer clear of this engine for a boat. My poor old 4.236U's might be hard to get some parts for, but then they hardly need any... ;)"

[amayers]

"I also have heavy blue smoke on startup when engine has not run. My engine was made in 1991 and had broken hours meter when I bought it. I suspect value guide seals may solve problem as it only occurs for 60-90 seconds on startup after sitting for some time. Engine has been reliable and I have changed the timing belt/water pump/tensioner myself. I found this to be a simple quick operation. I changed the timing belt on my 2005 Jetta TDI and found that to be a complicated time consuming task (for reference). While I appreciate Van Eerdwegh Marc's comments, I think I would never put a timing belt on any (I have done about 6 or so) motor with out a written procedure, as there are frequently nuances to this and I think Van may have just been lucky in the past or worked on super simple engines. I am guessing my M50 has at least 5000 hours on it and except for the low reliability lucas (now prestolite or some 3rd name) starter, has been an incredibly reliable and trouble free motor. To think that the valve guide seals (made of rubber) may be worn out after 18 years ... well this is to be expected.

Parts prices are astronomical ... but so are Volvo and Yanmar as I understand it.

Are there M50 owners that think this engine is unreliable? If I had a 1991 car motor, I'd be very happy if it was as carefree and easy maintenance as my M50."

[broeshart]

"Hello, We just bought a boat with a Prima Perkins 50 HP of 1989. About 2600 engine hours.
The engine had the problem of the STOP-button not working. The Button has been replaced with a new one, but the technician told that the previous button was not broken. The stop-button should work now, but is not yet tested. This will be tested when the boat will be put in the water in april 2010. In this discussion I see that other owners had the same issue.

1. I wonder what the cause and solution was for this problem.

2. The boat is going to sail for 6 month from April till oktober 2010. Now is the time to do some preventive maintanance in order to minimize risk of engine problems.
I wonder what kind of things should be done. (I will leave this to a technician) I am thinking of preventively letting change the distribution belt.
But maybe it is better to do nothing, since touching the engine with complicated jobs can cause problems. (Accidently touching timing belt?) (Replacing distibution belt sounds complex, but maybe it is easy ?)"

[amayers]

"Axel,

From the sounds of things, you personally will not want to touch anything on this engine but the dipstick, check the fresh water level and verify the strainer is not clogged. You need a competent mechanic (or time and desire to become one ... which is not very difficult).

The M50 design is different from probably any automotive engine you have ever seen, as it is NOT grounded (unless someone has altered it's original wiring). If you give your auto mechanic the service manual for the M50 and ask him to take a careful look at the engine wiring diagram, with particular attention to the grounding circuit ... it should only take a minute or 2 before he is scratching his head in puzzlement. The M50, as originally wired is grounded ONLY when 1 of the Start, Stop or Glow Plug buttons are depressed. As for your stop 'button' problem, the actual source of the problem is probably in the engine compartment. There are 3 relays on the aft port side of the engine near the valve cover(? by memory). One for each of the afore mentioned buttons. These are quite close to the raw water pump and hoses and generally also in the path of salt water flung around by the prop shaft
if there is a slight leak in the shaft seal or stuffing box. Check the operation of the relays and the wiring between them and the stop button. Ultimately there is a plunger that blocks fuel on or near the injection pump that the relay operates. As a stop gap or in an emergency, there is a mechanical lever on the injector pump that will allow you to stop the engine (can be reached from the front of motor on port side top).


If your mechanic is afraid of touching the timing belt when he changes the aux belt (alternator, engine driven compressor, whatever) run far and fast to get another mechanic. The timing belt is (better be!) behind a cover that needs to be removed, the aux belt(s) are plainly visible from the front of the engine.


The aux belt change (required in your case) should take someone with any level of experience on any auto engine, a max of 20 minutes ... I can change mine in 3 mins.

The Timing belt will take a couple of hours, will probably require an impact wrench to loosen the tensioner (needs to be replaced with the belt). The fresh water pump should also be replaced at this time ... anything else is foolish. See notes below about replacement interval (2000 hours or 6-8? years). You will want to rent special perkins tools from (among others) Transatlantic Diesel, Virginia USA. Buy the water pump, timing belt and tensioner ONLY from someone that will rent you the special tools. They are merely some pins (by memory) that lock down the top and bottom halves of the motor, and could be fabricated earily if you have the dimensions, but it is plain stupid to attempt to change/tension the timing belt without these locator pins.


If you are going to be the 'engineer' on a passage of any length, you need to become more educated on diesel engines and in particular your M50. There are books by Calder (I think) and others that will give you easy to understand troubleshooting. You will also need to buy a perkins M50 Service Manual (maybe $100 US from any Perkins distributor or Transatlantic Diesel if you don't want to hunt). You will NOT be saving money to skip this ... your chosen mechanic will need it, and in your spare time voyaging, you can read it for entertainment;~)



The age and hours on the engine REQUIRE that you change the timing belt if you don't have proof that it was done at around 2000 miles and in the last 6-8 years or so. Timing belts can can go bad in time with NO hours. If the time belt breaks on passage, you are done using you motor. On 'interference' engines (and I don't think the M50 is) breaking a timing belt will cost potentially thousands dollars of unnecessary repair (bent vales and punctured pistons). In fact the only way to cost effectively fix a 'valve crashed' older engine is to do a complete overhaul (if you are intending on keeping long term)."

[mve]

"Hi again,

I appreciate the comments. Thank you.


A.J.Mayers comments are very accurate.

I share his opinion that the 'stop engine' problem is probably not a consequence of a dysfunctionning of the button itself on the control pannel, but a default of the relay.



I also agree about how easy the operation of changing belts is. Aux belt is no problem at all. To change the timing belt is a bit more difficult, but still a very accessible mechanical work.

The Perkins instructions are to change the timing belt every 2,000 hours or 2 years.

Indeed is the timing belt protected by a cover.

The timing positionning of the engine is quite easy to find and operate.
Down, right side, through a whole and in the thooted wheel, to position the crankshaft.
Above, in front, under a special cover (to be taken out) to position the camshaft.
The only problem is to correctly block the injection pump, besause, when in timing position of the engine, it is pressed against one of the injection springs : one needs 2 special threaded stems (non metric thread) to tighten the wheel in that position.


After changing the belt, the most difficult operation is to put the right tension on the new belt, with what I feel beeing a quite imprecise system (eccentric wheel to be tightend).


I also agree on the fact one definitely needs to have aboard the Perkins repair manual !


And one last thing :
To my opinion, mechanic work has nothing to do with such a thing as being lucky !



I wish you all better experiences than mine with the M 50 !
I will probably use in the future a good old Perkins 4.108 or 4.154

Marc"

[marinerbob]

"Tks. to all for valuable info in recent posts. Below are my expereances after 18 months and 300 hrs of ownership.

1) I had the alternator modified to take an external 3 stage regulator. This action invalidated the starter circuit and I spent a great deal of fruitless time trying to correct same. The solution was to remove the starter relay ( 1 of 3 mentioned by AJ ) and wire directly to a spring loaded toggle switch on the panel.
2) as mentioned earlier I had the fuel pump fail. I have since read that the priming leaver on these pumps can put a sideways preasure on the pump arm which can disengage the leaver from the camshaft. I am not able to comment on the validity of this however I am advised that many owners install a small electric pump in parrallal with a shut off valve as a back up and to aid priming after filter change. This one is on my jobs list.
3)The standard Perkins installation is to have a Lucas oil/water separator between the tank and the lift pump. I have replaced this with a Racor combined filter and separator as the filter is very easy to change and with a clear plastic bowel you can see any water. Also you can't have to many filters before the injector pump.

Now onto blue smoke.

From recent posts this appears a common condition. The question is "at what point does it indicate a problem". Talking with our local engine shop these engines a quite common in this area,( Canada West coast ). The shop is familar with them. They report that they are a good engine but smoke on start up was always there even when new. If excessive and injectors are OK then probable cause is a worn or incorrectly set injector pump. AJ mentioned rubber valve seals which after 18 years may well be worn or hardened. Our shop said that this has not been their experiance.
As fuel consumption is increasing I am coming to the view that a worn injector pump is the probable fault. I hope to have this into a injector shop next week and will report again on results.
In browsing the web I found www.marineparts europe.com. They have full parts list and exploded views of the volvo MD22. Most of it is the same as the M50. It is easy to see why Marc was frustrated on lifting the valve cover. The "cover" is the top half of the camshaft bearings. Do not touch unless you have to.
Again, thanks to all for input. Bob }"

[theghost]

"I have a Prima 60, I would think the 60 and the 50 are the same apart from hp. My starter stayed engaged and burnt out and now I am trying to source a replacement, the mechanic tried two generics but neither worked so we are still looking. We also managed to find the problem with my stop button to, it appears that it does not go through one of the relays, it is wired direct from the button to the solenoid on the fuel pump. The switch puts 12+v onto the solenoid. The problem with my stop circuit is the connector plug on the engine loom, its very badly corroded and has 12v on the switch side but 0v on the solenoid."

[marinerbob]

"Peter, there is a manual stop leaver that shuts off the fuel above and behind the injector pump. if all else fails a pull wire to the panel ( the way it was always done in the past) would work.

To all who helped me with my blue smoke problem:-

The problem is more or less resolved. Sure it smokes on start up when cold and to a much lesser degree when revs. are increased when under load. Otherwise its just about nil. What did we do ? new timing belt, refurbished injectors and the use of a fuel additive. Also the engineer said running at 2200 rpm was to slow these engines should be run at 2600 to get to full heat and burn clean. I am not sure which was the most effective. A compression test gave 250 lbs on # 1 & # 2. did not do others. This is way down and suggests glazed walls. I think the fuel additive has cleaned the combustion chambers. We have not run enough hrs. yet to check fuel consumption but I am very happy with progress to date.

Bob."

[pavoird]

For the second time in 7 years I need to renew my heat exchanger (yes, the copper pipes) and it is hardly available, let alone reasonably priced.
Can anyone send a tip for immediate or quick purchase?

Can I get the piping out and still use the engine in the meantime? I know it would then cool with raw water, but it would be only temporarily as my technician would like to see if the pipes can be fixed, instead of buying the expensive new one.

Thanks for your reply
Pavoird, Holland

[keith 252]

I have a perkins prima in my fishing boat, i seem to be loseing a lot of automatic transmission fluid from the gear box, i think its heading out the exhaust ne ideas.?

[gyras]

Hi, I'm looking for a good mechanic to work on my Perkins Prima 50. I'm in Cape Canaveral (Merritt Island))
Thank you

[gyras]

Hello,

I would like to know if anybody can help me. I'm looking for a good mechanic to work on my Perkins Prima 50. I'm in Merritt Island (Cape Canaveral) Florida.

thankyou,

guygingras@yahoo.ca

[asailsman]

Gyras,
I have spent 10 years caring for my M50 and just recently completed a extensive rebuild (pistons, valves, seals, bearings, etc...) Is there a specific problem with your engine? I have a friend that has the same engine and we are always working/maintaining this engine. We are in St. Pete but maybe can help. Just a note, with proper maintenance and a good understanding of the negative earth engine it is a very reliable engine.

[gyras]

Thanks very much for the answer. I'am not very good in english but i'll do my best. My engine seems to work good but the oil pressure light, the key on buzzer, the RPM indicater and the cooling system light are not workiing. The boat will be in the water next week and I will try to fix all the problems. If I need any other information I will contact you. I apreciate your help already and feel in more confidence to know that I have somebody outhere that can help me

Thanks again,

Guy

[asailsman]

Good luck, try cleaning the contacts on the back of the instrument panel real well with contact cleaner. Check for bad connections and broken wires. The wires get real brittle inside the wire coating and can be broken and not obvious. When the starter and stop doesn't work on my boat it is usually dirt or corrosion on the back of the push button relay on the instrument panel. You'll see it when you look at the back of the instrument panel. Let us know how it goes!

[gyras]

Thank you and I'll let you know if I find something.

[GALAWA]

I have a Jeanneau Sun Magic 44 with Perkins Prima. So far I service the engine by myself and I ve done as far as replacing the Timing Belt and the fresh water pump

Wich parts of the water pump did you have to replace ?
A mechanic has quoted to me some 850$ worth of parts alegedly required to fix my water pump : Inluding shaft (250 $), scallop (70$) , and cover (70$)
I cannot see the parts thez mechanic proposes to replace as my boat is wintering abroad

[GALAWA]

Quote : [just a few weeks ago a bizarre problem involving the adapter plate between the engine and the raw water pump ]
Wich parts of the water pump did you have to replace ?
A mechanic has quoted to me some 850$ worth of parts allegedly required to fix my water pump : Inluding shaft (250 $), scallop (70$) , and cover (70$)
I cannot see the parts the mechanic proposes to replace as my boat is wintering abroad.
What would you think

[GALAWA]

M50 excessive vibration.
My PERKINS PRIMA vibrates heavily , really shaking my 40' sailboat , at low revs, wether in neutral, or with a gear engaged
I had the silents blocks checked : They are OK
The mechanic suggested trouble with the injection, yet my M50 runs smoothly above 900 RPM
Does someone have a clue ?

[shakey]

G'day,
It does sound like it could be a injection issue. A quick easy test is with engine at idle [ vibrating] undo each injector lead one at a time for 5-6 secs before retightening the one that indicates the least reaction is the u/s one. Are you running a Pto drive??

[GALAWA]

The mechanic who checked the silent blocks did try to neutralize the injectors one by one but this test was inconclusive;
No apparent change in the engine behaviour

Yet the mechanic maintained that the vibrations where probably related to injection
To reduce vibration, we increased idle setting from 500 to 800 revs
And now it shakes violently in forward fear at idle revs

[Tasemaro]

Quote : [just a few weeks ago a bizarre problem involving the adapter plate between the engine and the raw water pump ]
Wich parts of the water pump did you have to replace ?
A mechanic has quoted to me some 850$ worth of parts allegedly required to fix my water pump : Inluding shaft (250 $), scallop (70$) , and cover (70$)
I cannot see the parts the mechanic proposes to replace as my boat is wintering abroad.
What would you think

If this is the raw water pump (mounted on the rear of the engine) then it's probably about right. The expensive part is the shaft, although if it IS the raw water pump I can't understand why the "Scallop" (I'm guessing "body") would need replacing. Unless the pump is in very bad condition and the brass retaining screws that retain the cover have all seized/broken. Please confirm which pump it is.

I have experienced that same problem with the "adapter plate" and I had to replace the shaft and the "shaft drive dog" that connects the drive from the end of the camshaft to the pump. I apologise for the name, "shaft drive dog", but I can't think what it could be called. The previous poster was correct that mis-alignment of adapter plate causes large amounts of wear on the end of the shaft and the "dog". The best way to align the parts is to use the Perkins tool, but there is another method which worked for me.

My engine is from 1993 and had done 4000+ hrs when I got the boat (the hour meter was broken). I have put a further 3000+ hours on the engine in 6 years and aside from regular oil, filter and timing belt changes has required very little maintenance.

I agree with a much earlier post that if there's no oil leaking out of an M50, then there's none in it! I'm sure Mr. Perkins never intended that his engine should leak oil, but they all seem to drip just a little. Oil's cheaper than removing the engine for new seals which may not even solve the problem.

I also agree with an earlier poster who said, unless there's something wrong, leave the valve clearances alone - this goes for nearly all marine diesel engines. I can't understand the people who feel the need to check the valve clearances every time the engine is stopped for more than a day; you wouldn't do it with a car engine. A friend of mine checked and adjusted his valve clearances so often that in the end the valve adjuster lock-nut on one of the valve assemblies wore out and he couldn't tighten it any more. The result was a catastrophic failure some hours later when the nut first fell off the adjuster and then somehow got itself under the camshaft resulting in the camshaft jamming and the resultant carnage at 2300 rpm!!

Let me know which pump it is!

[Funsurfer]

Does anyone have a gas emissions certificate for the EC for the Perkin Prima 50 or could help me to find one? Thanks