Oil & Fuel Yanmar YM155D Transmission Dipstick

[stevejjones]

Hello, my name is Steve and I live in Scotland. I recently purchased a used Yanmar YM155D with front end loader and Polymark D200 backhoe. It all works mechanically, but does need some TLC. I got it for a good price though and the tractor has been very useful so far.

The transmission fluid needed changed, so I went ahead and drained it and put new transmission/hydraulic oil in. I attempted to remove the transmission oil filter cover so I could remove and clean the filter, but it seemed basically impossible to remove without first removing the backhoe frame from the tractor. I'm assuming the filter has not been cleaned in some time.

The transmission dipstick was really tight to remove and the plastic/rubber handle was missing from it, I managed to remove it with pliers. I was then unable to re-insert the dipstick because of the rubber grommet in the hole. I removed the rubber so I could get a better look and then attempted to put the dipstick back in to see how far it would go. Because my hands had oil on them the dipstick slipped out of my fingers and ended up dropping right into the transmission dipstick tube!

I removed the 8 bolts holding on the transmission cover so I could remove it and retrieve the dipstick but it won't come off. I've used the tractor since and everything seems fine and the front end loader seems much smoother since changing the oil. If I shine a torch into the transmission oil fill hole, I can see the oil level which looks fine. Can anyone help answer the following questions, I'm not a mechanic so bear with me:

1) Any tips on how to get the cover off the transmission?
2) Any other suggestions on how to get it out of there? (I've ordered a grabber tool online, but it's quite a small hole for the dipstick so not sure if it will fit)
2) Will the dipstick do any damage to the transmission if I leave it in there? (I've got the service and owners manual, but I can't tell from the drawings exactly what's inside the transmission where the dipstick is, I'm assuming there is a dipstick tube)
3) Can anyone provide the dimensions of the dipstick, so I can make or source a new one? (As far as I can tell the dipstick tube or whatever is in there seems big enough that I could fit another one in even with the lost one left in place)
4) How important is removing and cleaning the transmission oil filter? (I've not removed the backhoe yet, but looks like it might not be a 5 minute job to do this)
5) Also, none of the dash indicator lights are working. I've checked the fuses and none of them are blown, so I'm guessing it's either the wiring or the bulbs. Does anyone know where in the UK I can get replacement bulbs?

Thanks for reading and any help provided would be much appreciated!

 

[rScotty]

Hello Steve,

Click on my name & send me your email in a PM (personal Message) and I'll respond with a .pdf shop manual for the YM155D - unless maybe you already have one.
I gave my hard copy of the shop manual away, but still have a YM155D parts manual, which always seemed to me to be better than a shop manual for the types of questions you are asking.
There are usually Yanmar parts manuals on Ebay. $60 to $100 USA seems the going price. You want the parts manual with the green paper cover, and the shop manual with the red plastic covers. Look around on ebay.

Maybe you will get away with running it with a dipstick kicking around in there. I don't think I'd feel good about that. I did go out just now to measure the dipstick on oour YM165D (same tractor) - a tractor that I hope to finish rebuiding someday - only to find that the guy I hired to flush it and lube it for storage must have simply took the money and left it full of water. It's been years. So the dipstick is stuck. I'll try to extract it carefully & measure it this week.

NO, THERE IS NOT ANY DIPSTICK TUBE. Your dipstick is knocking around in there somewhere. I would use a cheap endoscope and a grabber. You can probably get both for $100 bucks. Or better yet, just take the darn cover off.

About the cover and taking it off, I'm assuming that you took the shifter cover and lever off first? Or are you trying to get the both top covers at once? I don't see any reason either way wouldn't work. I see nothing in the exploded parts diagram that would stop you from simply taking them off, but in that case why is there two covers?? That is suspicious. Of course it is true that Yanmar's original black felt gaskets were heavy felt impregnated with a sort of epoxy facing that sets up very solid. It is possible that it may simply be a stuck gasket. Expect it to tear. There are better ways to seal gaskets today, but it would be nice to have the gasket in hand as both cover gaskets are thick enough to qualify as spacers. If you do tear it, just leave it as it and reassemble with a thin coat of Permatex silicon sealer on one the torn face. The silicon is allowed to almost dry before assembly, and the other face is often coated with grease. That way it seals but comes back apart.. Use a this as coat of paint coat of silicon and let it cure to rubbery before assembly so it will not squish out stringers of goo into the transmission. Today, even old gaskets used properly with a silicon sealer are infinitely reusable. But the old gaskets by temselves always tore.

You should get that 3-bolt bottom filter cover off and clean that filter too. Letting it get clogged can starve the hydraulic pump - which is a horribly expensive device. But again, get all the gaskets in hand first.

If all your dash lights seem right but not working it may well be the lighting portion of the ignition switch. They did suffer from corrosion. Some switches come apart, others you have to buy new.
I'm guessing that's enough for now. Let me know how it is coming. Photos?
Luck,
rScotty

 

[Altona]

Hello Steve
I had a similiar problem a couple of months ago except mine was the hi-lo shifter pin thing which had broken off (its like a hook inside the tranny that fits into the shifter fork). A quick google makes me think your 155 is similar in that aspect to my 240d. I removed the the larger (bottom) 4 bolts which expose a wider opening into the tranny. If you take off the top you're into the shifter mechanism . From there I used one of those magnetic pickup tools that extend out to a meter. The broken piece was right down at the bottom of the pan. Had to slide a couple of the gears up and down their respective shafts to make a big enough gap to carefully bring it up to where I could grab it. When I removed the 4 bolts on the cover it was on there tight after 40 years so it took a little repeat tapping with a brass hammer to free it up. When you lift it up note the shifter fingers are there so becareful where you place it down. As I usually expect screw something up I took a photo of where the gears were on the shafts with my phone so it made it a snap to put back on. I repaired the gasket in a way similar to rScotty (his is better, use it) It does need to come out of there though. I was lucky, don't know when my shifter piece broke as I don't go between ranges often and it had dropped straight down and was heavy enough it just sat there. Good luck with it. Photos of the area around the filter cover may help us understand that issue but I would definitely get it out and cleaned. It is just one of those things you don't want to mess with. Taking the cover off is easy, much simpler than you may think. Trust me, if I can do it you'll be able to. Good luck and keep us advised.

 

[Altona]

This is what mine looked like with the cover off

 

[stevejjones]

Hi guys. Thanks for your help. I was able to remove the shifter and then the transmission cover with a bit of persuasion from a mallet. The shifter cover gasket was in pretty good shape, but there was a few tears on the transmission cover gasket. I was able to retrieve the dipstick, I just reached in a grabbed it. There is a small nick out of the dipstick where it must have touched one of the gears. It was already bent and the handle was already missing, so I'll just need to make a handle out of some Sugru or something.

Whilst I had the transmission drained I attempted to remove the transmission filter cover. I got all 3 bolts out and was able to move the cover a little, but I am unable to remove the filter, due to the front end loader support frame in the way. I think I'll have to remove this if I want to clean the filter. The front end loader support frame is attached to the backhoe frame. Which is great that's it's nice and strong, but I don't know how easy it will be to remove. I think that's a job for another day, so I bolted it back up again. Everything else looked fine in the transmission and it's had a good flush from 2 lots of new tractor oil.

I used some sealant on the gaskets as described above and closed everything back up, everything is working fine. I've attached some pictures for reference.

 

[Altona]

Hi Steve, Glad you got the dipstick out and your problem is resolved (at least that piece of it). You shouldn't have issues with the gasket repair, they are above the oil level and the system isn't pressurized. Sounds like a ton of work to change the hydraulic filter but in the long term you'll want to do that. On my 240D, which has a FEL, the support frame has a curve in it to allow the filter to come out straight. This particular FEL would appear to have been made in Chicago but specifically for this Yanmar. Don't know the maker because the plate on it says "Yanmar, Chicago Illinois". I think it came with tractor new as a unit as it is the same colour as the tractor (same green as yours).
That is a good looking and worth the time to invest. When you're ready to tackle it perhaps you can have the FEL frame altered so in the future you won't have to go through this. When you're ready to take it on let us know and I'll crawl under mine and take some measurements and photos and post here in case it helps.
Cheers and stay well.