TAMD41b Oil from Around Injector

[Dazzajon]

Hi all,

I hope everyone has had a great Christmas.

It’s getting to that time of year now where I’m thinking of the jobs I need to get the boat ready for the new season.

I’ve got a VP TAMD41b and it appears a small amount of oil is leaking from around one of the injectors. It’s really not very much and seems to only leak when at cruising speed so I’ve just been leaving some taupe paper wrapped around it so I can keep an eye on it without it leaving a mess but I am wondering if anyone has any ideas on how to solve?

Thanks in advance for any suggestion.

Cheers
D

[DougR]

So...did you try any of the suggestions that were given in response to your October inquiry on the same topic? What were the results?

DougR

[Dazzajon]

Originally Posted by DougR

So...did you try any of the suggestions that were given in response to your October inquiry on the same topic? What were the results?

DougR

Yes indeed I did. I’ve thoroughly cleaned the cover to make sure there is no residual fuel, I’ve tried to do the bubble check and I have also checked the various other connections.

The only thing remaining is to remove the injector sleeve and replace but I’m only really a novice so for me this is a last resort so wanted to see if there were any other avenues to explore before doing this or indeed whether to just leave alone seeing as its only minor :-/

Cheers
D

[Wotname]

Originally Posted by Dazzajon

Yes indeed I did. I’ve thoroughly cleaned the cover to make sure there is no residual fuel, I’ve tried to do the bubble check and I have also checked the various other connections.

The only thing remaining is to remove the injector sleeve and replace but I’m only really a novice so for me this is a last resort so wanted to see if there were any other avenues to explore before doing this or indeed whether to just leave alone seeing as its only minor :-/

Cheers
D

IMO.
It might not remain minor, time to take the plunge with pulling the injector.

If you leave it and if it stops leaking by itself, then it will be corrosion that is sealing it and this will make much more difficult to remove in the future.

[Dooglas]

Originally Posted by Dazzajon

The only thing remaining is to remove the injector sleeve and replace but I’m only really a novice so for me this is a last resort so wanted to see if there were any other avenues to explore before doing this or indeed whether to just leave alone seeing as its only minor

Volvos of the 40/41/42 series use a copper crush washer to seal the injector to the engine. They are somewhat finicky and only usable once. If you decide to do this job yourself, buy a package of them and be careful to torque to spec. It may take more than one try to get a good seal. If you don't have much experience, it may be advisable to have a mechanic do this for you. How many hours on your engine since a top end rebuild? May be time to have the injectors rebuilt anyway.

[DougR]

As mentioned earlier, there is no engine oil associated with the fuel injector. If you have an engine oil leak near the injector it is probably coming from the main valve cover gasket which sits immediately adjacent to the injector, or one of the three smaller valve cover gaskets. A little bit of spray foot powder in the area might help isolate the leak.

If you have a fuel oil leak it could be coming from the high pressure fuel line on the top of the injector or the return line attachment on the side of the injector.
Wrapping several wraps of string or taupe paper around the injector, both below the high pressure fitting and also below the return line fitting should help isolate the source. If the leak is from the return line copper washers, fresh washers should resolve the leak. If from the high pressure line it's possible the line end is incorrectly aligned with the injector and requires adjustment, or perhaps the line is damaged and requires replacement.

It's also possible that the injector is leaking where the tip screws on and the fuel is working its way up the copper tube. If so this is something for an injection shop to take care of.

You will have to make the determination of where the oil is coming from, and that's a process of elimination.....

One other thing....the information offered concerning crush washers beneath the injector is, I believe, incorrect. During the entire production life time of this series of engines there never was a washer used below the injector. The injector body sealed directly on the copper sleeve. Perhaps this has changed recently, but the online parts books that I use show no washer.

DougR

[Dooglas]

Originally Posted by DougR

One other thing....the information offered concerning crush washers beneath the injector is, I believe, incorrect. During the entire production life time of this series of engines there never was a washer used below the injector. The injector body sealed directly on the copper sleeve. Perhaps this has changed recently, but the online parts books that I use show no washer.

You are, of course, correct. I described this poorly. The washer which gave me so much trouble was on the body of the injector. And yes, I presume the OP is talking about a FUEL oil leak.

[Compass790]

I had trouble with injector leaking from interface with cylinder head, easy fix was a thin smear of Loctite 518 mastergasket on injector face. Others may scream "you can't do that" but it works on our 23:1 compression diesel. But you need to know where leak coming from as others suggest

[-bliss-]

A few years ago I had the same problem on my 31- engine (which is the four cylinder version of your six cylinder 41- engine)
I´m by no means a diesel expert, so I consult a well known old school VP mechanic who has put his kids through collage rebuilding green engines. Luckily, he promptly presented a trust worthy and simple solution to my problem.

The first thing he said was not to remove the injector sleeve!
First of all, if you do this without draining the coolant system, you will flow the cylinders..
Secondly, there´s no guarantee you´ll be able to get a perfect fit for the new sleeve. Chances are, you´ll end up struggling with a bigger leak than before. He even called this operation a Russian roulette..

I was instructed to scrape off and vacuum as much of the solidified gunk as possible before removing the injector. Then clean the injector and add a layer of copper paste to the body of the injector before putting it back.
If you are afraid some remains of the build up has fallen into the cylinder during this process, you can turn the engine over for a second or two. The compression will blow the residual out.
After replacing the injector, go a bit easy on the nut on top of the claw holding the injector. Don´t be tempted to overtighten, especially on warm engine, as the bolt might crack when engine cools off..

You also have to replace the small copper washer on the fuel lines. You need one washer for the fuel supply, and two for the return line of each injector. The washers are 8 mm inside diameter, and 11 mm on the outside. (Probably the equivalent of 5/16” and 7/16” in the imperial world)

After reassembling, fire her up, then release trapped air by opening the supply- line for a second or so until it squirts diesel.

Don´t be disappointed if you still can feel (and hear) the leak after firing up. Tighten the nut on top of the claw gently as needed, and after an hour or so on normal temperature, the copper paste surrounding the injector will cure and tighten the remaining leak.

According to my maintenance log, this was 153 engine hours ago, and It´s been running clean ever since.

Beautiful and extremely reliable engines by the way! During the eight years I´ve owned this vessel, this minor leak is the only engine related problem I´ve encountered.

Good luck!

-kjetil-

[sazarac]

Originally Posted by Dazzajon

Hi all,

I hope everyone has had a great Christmas.

It’s getting to that time of year now where I’m thinking of the jobs I need to get the boat ready for the new season.

I’ve got a VP TAMD41b and it appears a small amount of oil is leaking from around one of the injectors. It’s really not very much and seems to only leak when at cruising speed so I’ve just been leaving some taupe paper wrapped around it so I can keep an eye on it without it leaving a mess but I am wondering if anyone has any ideas on how to solve?

Thanks in advance for any suggestion.

Cheers
D

First, is it diesel or motor oil?

[Dazzajon]

Originally Posted by Dooglas

Volvos of the 40/41/42 series use a copper crush washer to seal the injector to the engine. They are somewhat finicky and only usable once. If you decide to do this job yourself, buy a package of them and be careful to torque to spec. It may take more than one try to get a good seal. If you don't have much experience, it may be advisable to have a mechanic do this for you. How many hours on your engine since a top end rebuild? May be time to have the injectors rebuilt anyway.

There are around 1110 hours on the engine but the previous owner had the injectors overhauled early on in the year.

Rather frustrating as obviously I had a survey on the boat before purchase and there were no leaks present but by the time I’d done the 5hr passage to get her home after purchase there it was.

[Dazzajon]

Thanks for the various replies.

I tried running the engine in the berth but I could not see any evidence of the leak, it only seems to present itself once I’ve taken the boat for a good run at cruising speed at which point it’s a bit difficult to safely be in the engine bay for a good look.

In the end I narrowed down where the leak is coming from by wrapping various pieces of taupe paper around the various connections and seeing which piece is dirty and it’s definitley the piece I had wrapped around the injector.

I’m really no mechanical expert but it seems the oil is coming from around the injector. And to confirm it’s definitely not diesel because it doesn’t smell as such, it really does appear to be oil.

To further thicken the plot I have chatted to my local engineer who says (as some of you seem to concur with) that there is nowhere for the oil to come from other than the rocker cover but I still maintain as far as I can see the oil is not coming from there.

So basically I’m baffled and not knowing what to do. As I’m convinced it’s oil, I don’t want to go removing injectors and sleeves etc if there is no way the oil can come from there in the first place.

[DougR]

So if your local engineer says that the only place engine oil can be coming from is the rocker cover, and you are sure it's engine oil, replace the rocker cover gasket.

DougR

[-bliss-]

Your leak is oil. At least that´s what the swedish mechanic who has worked on these engines all his work life said to me. He said it´s totally normal for an old VP-engine to let a little oil pass up to the top.
If you remove the oil fill cap while the engine is running, you might feel a a slight air pressure on your hand. This pressure is air and possibly a little oil. It´s totally harmless, just a sign of an engine with quite a few hours under it´s belt. Once again, I´m not claiming to be a diesel expert, just passing through what I assume is relevant information from a guy who probably could rebuild these engines blind folded.

Having removed all my injectors, I can say for certain there are no copper crush washers sealing the injectors to the top of the engine. As previously mentioned, the only copper washers involved seal the feed and return fuel lines.

I think it´s relevant to include the 30- something engines to the comparison as well, since 30 something and 40 something basically are the same engines only in different sizes. The 30 series being four cylinders, approximately three liters displacement engines (hence 30- something) and the 40 series being six cylinder, approx. four liters displacement. I´m stressing this, since information regarding the 30 something engines might be relevant to more sailors than the 40 something engines, since the 40 / 41 is a very big engine, rarely seen in sailing vessels, at least in my neck of the woods. The 30/ 31 on the other hand, was a very common engine for heavy displacement Swedish premium sailing vessels in the eighties and nineties.

Try the copperpaste- trick. I´m positive you´ll be satisfied.

Best of luck,
-kjetil-

[-bliss-]

PS:
I had the same problem in my long gone Mercedes E- class common rail diesel car engine. The smelly gunk on the top cover, surrounding the injectors was described as solidified oil leaking up to the cylinder top due to worn out O- rings at the bottom of the injectors. At least that’s what the mechanic who fixed the car said, and what was specified on the bill I paid.