Volvo A20 details

[Tony Wells]

Hey guys, I have a Volvo A20 in the shop with several issues. This is one confusing truck. For some unknown reason, many ID tags are absent, so I do not have a VIN to even start with. I have two major concerns, and a hot job (naturally). First, and most aggravating, is the 2 piece exhaust manifold. Over some time, the seal rings have failed and of course the exhaust gases have eaten their way merrily through the female (socket) end of the other half of it. I had the guys pull it, not really seeing the backside where all the damage is. I had planned on welding it up and re-machining the female (rear) section and replacing the seal rings. Well, as we all know, plans don't always work out. Hitler had a plan, as did George Custer. Theirs didn't work out so hot either, thankfully in Adolf's case, and too bad for Custer and his men. This rear half is too far gone to even think about building up for machining. I might be able to cut it off and weld on a entire new re-creation of the socket, but I'd rather not have to go there.
Now to get a replacement all I have is the engine s/n. Volvo eventually came up with a quote and it's more by far than I want to pay. So....I'm on the hunt for a used one. If anyone has a possible source, I'd sure appreciate hearing about it. The engine s/n is TD71G *287*30490*. All I've found up to now is that it's a D71 family engine, and is popular in the marine industry. I've seen pictures of those manifolds, and they are not at all like this artic. So I'm stuck at this point, not wanting to spend the money with Volvo.

The other thing is the power steering. At temp, it tends to shudder and takes more than normal effort to turn the wheel. Acts like it has the wrong oil in it. But I don't know what should be in it. It appears to be plumbed right along with the rest of the hydraulics, although some references on older models I see the fluid as being Dex IId.

That brings me to a 3rd sub-problem. I don't have any documentation for this truck. I don't know what year it was made, I don't know enough to even buy a manual, which I want to do. I see a few on that auction site, but they are all A20A, B, or C titles. I don't know which one to buy, nor how to determine that, now that some kind soul has deprived me of all the normal markings. Can anyone tell me the differences? Or at least with that engine s/n tell me what year it might be?

Meanwhile it sits while I fight a battle with a feller buncher.

 

[sfrs4]

Right i can find your machine (that is as long as the engine is original) BUT Volvo's date records only go back to 2000, using a chart we started compiling years ago of different machine serial numbers and years of manufacture your machine is an 88-89 machine, and the serial number is 2086 ( again as long as the engine is original )
the serial number is more important than the year.
your first problem with the exhaust the part you require is it the end that doesn't have the turbo bolted on? if so i have a good used one on the shelf. plus the socket and seals as new parts
the steering really could be anything but a good place to start could be the volume control valve slightly rectangular looking block under the cab
so to answer the last question you have a straight old A20 (no suffix) and approx 98 build year (again as long as the engine is original)

 

[Tony Wells]

Right i can find your machine (that is as long as the engine is original) BUT Volvo's date records only go back to 2000, using a chart we started compiling years ago of different machine serial numbers and years of manufacture your machine is an 88-89 machine, and the serial number is 2086 ( again as long as the engine is original )
the serial number is more important than the year.
your first problem with the exhaust the part you require is it the end that doesn't have the turbo bolted on? if so i have a good used one on the shelf. plus the socket and seals as new parts
the steering really could be anything but a good place to start could be the volume control valve slightly rectangular looking block under the cab
so to answer the last question you have a straight old A20 (no suffix) and approx 98 build year (again as long as the engine is original)

Well, I need both halves really but have not found anything used yet. So send me a price if you will via email preferably. I’ll keep looking for the turbo end.

Thanks for the information on what I’ve got here. Also for a direction to go looking at the steering. I appreciate all the help.

T

 

[Tony Wells]

Well, I've had no success in locating the turbo end of the manifold, so I am looking at repair methods. I'm thinking of machining both parts of the manifold smooth round and simply getting some high temp stainless (T409) flex tubing and just clamping a piece to bridge the two halves together. Walker makes a braided flexible coupling, but it's designed to be welded to exhaust tubing. As far as I know, welding stainless to CI isn't feasible. I have heard that TIG brazing with silicon-bronze rod has been done, but I don't know personally of an instance where it was used on an exhaust manifold. So I have my doubts about trying that.

 

[sfrs4]

Sorry, no luck my side of the water either. it's one of those things that i'll not have for years then get a couple of machines in to break at the same time!

 

[Tony Wells]

I appreciate you looking for me, sfrs4. I guess this is part of the deal when buying overseas built equipment. I should be complaining about nothing being done to fix it until now. At one point it would have been workable to weld up and machine back to spec. But nobody mentioned it if they knew about it, which they should have. Now we have this situation.

If I get this worked out, I'll post some pics of the result. It may help someone down the line.

 

[sfrs4]

Yeah it's more a case of older and rarer equipment than overseas, i have a VERY good network of new genuine, aftermarket and good used suppliers of Volvo parts, and none of us can find that manifold, if it had been the later and less rare TD71KF I have both halves sat on the shelf as good used parts. but the orientation of the turbo flange is completely wrong to fit it I've been informed.

 

[MKTEF]

I made a search at www.mascus.no and found at least 3 engines sold for parts. Or search for "volvo a20". I am guessing here, but you are looking for the one With the manifold outlet directly upwards and the turbo on top.

 

[Tony Wells]

That would be the one, MK. At this point, I am setting up to machine off the burned out socket of that side of the manifold. I was able to remove the connector nipple with seal rings from the other side and it cleaned up pretty well and I think it will do. When I get the lengths figured out, I'll machine the old socket off and turn a smooth round surface back to a shoulder and take a piece of 17-4 and replicate the profile and size of the original. Once I have a round true OD on the manifold, I'll bore the repair part to about 0.002 interference and shrink it on. As long as the lengths work out, it should go together like a new one. I have ordered new studs, nuts, spacers, the nipple with the 6 seal rings (which are merely spirolock snap rings and a gasket set all from Volvo. Supposed to be here tomorrow so I know how my weekend will go. I'll put up a few pics in case someone else needs to do something similar. There will be no welding or brazing on this repair. I'm counting on the shrink fit to seal and hold everything in position.

 

[Tony Wells]

So, I ended up giving up on finding a replacement. I ordered all the appropriate hardware, had the turbocharger rebuilt, and did a little machine work to repair the burned out end. I did get the connecting nipple from Volvo, and made a sleeve to fit it on one end and made the sleeve about a 0.002 press on the manifold. A little heat and it slid on and once cooled was plenty tight. For backup, I did pre/post heat a braze job also. Since the other half of the manifold was not burned thru, I didn't make a repair sleeve for it, but it was fairly pitted. That concerned me, so I sought and found a paste type product that was rated for continuous exposure to 2000° F and basically "glued" the new nipple in that side, and since I had machined the sleeve to fit the new seal rings just slid that end together. Worked out just fine. Pics if you're interested.

But now, although it runs great with a tight manifold and new turbo, I get a phone call about it not wanting to engage the transmission and a melted relay of some sort in the left hand dash access panel. Sure enough, when I get there I find a melted plastic Hella box with TBB52 and a few other numbers.....german language. It's the flasher module, and there was what I'd guess was a 1 watt resistor that had actually burned a hole through the PCB. No blown fuses anywhere. What this has to do with the transmission is beyond me at this point, if it has anything to do with it at all. It was driving fine before we removed the manifold and turbo. So I suppose Monday I'll go see if I can help figure out what's going on. It so happens that Land Rover uses that flasher module in several 24V mil vehicles. But that doesn't make it easy to find. Even that auction site listed only 1, and it was £75 or so and too long getting here. I don't think the intent is to make it road legal anyway, so I think we can live without the emergency flashers.

 

[Tony Wells]

I think we have no real need of that flasher module, and if I were a betting man, I'd bet two things: There is a short that caused the meltdown in the first place, and second, there is not a complete set of lights on the thing. So unless we need to get it on the highway all legal and everything, there's a lot more to do than fix the lights. .

Since there is familiarity with these machines here, I'd like to run a couple of things by you guys. I feel bad doing it, but I can't seem to locate a service book for it, in English anyway. I found one on ebay, and was about to buy it when I noticed it was in German.
Ich spreche, lese, esse, atme oder schlafe nicht auf Deutsch. Ich bin halb ungarisch, aber das hilft nicht.

At any rate, I am puzzled by the behavior of two systems. First, the steering. At times, perhaps 50%of the time, it seems to take inordinate force to turn the steering wheel to the right, even when moving. Other times it could be driven with one finger. If I understand the system, it is a manual steering gear, basically, but at the input end there is valve body, for lack of proper term, that seems intended to control the fluid flow to the steering cylinders. Presently, it has a leaky input (front?) seal, but I am suspicious more of the internal components. It never requires extra force to turn left, so I suspect there is a pressure imbalance in that valve body. Right now, it's usable, but I don't want to damage anything, or listen to whining drivers. If it's just a leaking seal, I can live with it for now, but if there is something going on internally, naturally it will get a new seal when that is adressed. But I can't justify pulling it for just a seal right now. As far as I can tell, that's all there is to the steering control circuit.

The other thing is probably stupid simple. When you stop the machine with the service brakes, it does not want to move again readily. In fact, in Drive, it takes a lot of throttle to get it out of its tracks, if it even will. Seems that is very hard on the transmission. Manually dropping it to gear #1 (Low), it still take a bit of throttle, but will move. Something pops (best description) and off it goes. Then it drives around normally (except for the steering) as long as you don't engage the service brakes. Coast to a stop, gently throttle it up and away it goes. I suspect something it sticking in the brakes. But I come back again to a lack of documentation and the mechanics are hesitant to just jump in. If I weren't disabled and not really supposed to do heavy work, I'd dive in. I'm not scared. But they apparently are.

I'd appreciate any comment or insight you could offer, or things to look at/for for either of these issues.

Many thanks for your help so far,
Tony