Siezed hand throttle B1600

[Sam66]

I recently bought my first tractor a (Z)B1600 with a couple of problems.

The hand throttle lever is siezed solid (foot throttle works fine). The tractor didn't come with any manuals and so far I haven't been able to find any online for dload or purchase (I'm in the UK).

This shows the problem part, viewed from the engine bay:

So far I have drenched it all in WD40 and then knocked it about a bit with a large hammer The nuts and washers (marked with green x) at the bottom came off easily. The bit marked with blue x which should rotate does not do so but I managed to move it down the shaft by giving it a couple of solid knocks from above with the end of a bar. All the bits above, (marked with pink x) do not move at all. My next step was to try and remove the two pins (marked with red x) but they do not seem to be allen bolts as I first thought.

Does anyone know if they are just friction fitted pins? Am I safe to drill them out? Will this even help solve the siezed hand throttle lever?

Not having any manual (or experience) I would appreciate advice from anyone.

Once this is fixed I have an oil leak from the bottom of where the pto exits the tractor, but I'll save that for another post

 

[cmorningstar01]

I would be very careful about tapping or banging on the part with the blue X's because if you break it it may not be that easy of a part to replace, The pins in the collar shaft may be press fitted, Have you tried to apply any heat to the area between the pink X's and where it goes thru, Maybe with a little heat from a torch and the use of a pair of vise grips or small pipe wrench you would be able to get it to move.

 

[Sam66]

Thanks for the quick response. I don't intend banging that part any more now I know it is movable - luckily it's pretty solidly made though.

I haven't tried heat yet, did think about it but not knowing the construction I wasn't sure if there were plastic or rubber parts inside that might melt. I'll give it a go and see what happens. I would quite like to get it apart just to see how it goes together and what caused it to seize in the first place.

 

[cmorningstar01]

I haven't tried heat yet, did think about it but not knowing the construction I wasn't sure if there were plastic or rubber parts inside that might melt.

It is possible there is a nylon or plastic bushing in there but if it will not turn then it really does not matter, I doubt there is though because it is not like there is a lot of fast constant movement on that piece.

Are the pins solid or are they roll pins, Either way you should be able to drive them out with a drift punch, Are you sure the restriction in movement is at that location and not above it?

You may be able to get a parts manual from the below link

http://www.tractorsmart.com/PartsBooksKubota/NeedPartNumbers.htm

 

[Sam66]

Thanks for the link but they don't list manuals for B1600, it seems to be one of the more obscure or short lived models.

I'm pretty sure this is the seized bit although the bush above through the instrument panel is also pretty rusty (this point does have nylon bush/washer thing):

The pins are hollow, I had a quick go at trying to knock them out but they are solidly stuck in there hence my idea of drilling them - since they are hollow I expect them to drill out easily enough. I'll try the heat and if that doesn't shift it then I'll have a hunt around for a drift the right size.

 

[Stubbyie]

Try using a specifically sized roll-pin punch. Those hollow pins should come out. I'll bet you'll find drilling that spring steel less than fun and the bit might drift off one-sided following the seam in the pin and get into softer metal damaging something else. Roll pin punches typically available from machinist and machine tool equipment catalogs. Try Kroil from KanoLabs.Com. Best stuff around. Punches should be from Travers Machine Shop Supply or Wholesale Tool Supply in the U.S.

 

[DBCSteve]

One idea is to look at various parts manuals from this web site:

http://www.kubotabooks.com/AutoIndex/

I downloaded and opened the parts manual for a B1550E, guessing it might have a similar setup to yours. Page 83 shows a schematic of the accelerator lever setup, which might be helpful. Unfortunately, no parts manual on that web site for your B1600.

 

[B7100]

As mentioned in stubbyie's post,those roll pins should drive out with the right size drift.
A mistake often made is to use a tapered or too small a punch which tries to go down the centre of the roll pin which spreads it tighter.
When you get the correct size try and get a helper to hold a very heavy sledge hammer or big chunk of metal tightly against the opposite side of the shaft so your hitting against something solid to reduce the spring effect which soften the blows.
Dave

 

[Sam66]

Thanks for all the advice, I tried heating with a torch but it didn't seem to help.

Probably should have been a 15 minute job with the correct drift. Not quite sure how but it turned out to be about 2 hours using a variety of improvised tools such as cut down hex keys, bits of socket extensions, torx bits, screwdrivers etc Got them out in the end though

Unfortunately I have more work to do. The bit the pins went through appears to be seized on to the bolt which protudes down, this bolt has a flat on one side and is tapered as well (cotter?). Should be (hopefully) straightfoward to knock this out from above once I find a length of metal the right diameter.

Will post a pic of all the bits once everything is dismantled so anyone else with this problem will at least know what's there.