TheHaflinger.com

Not only did I manage to break the silencer off Lurch and cause him to sound like a MACK truck all the way home from the Treffen, I managed to drop the Dynastart nut and outer pulley off him. As it turns out, I have all the pieces and currently have them installed using only a few of the washers / shims because the thread is stripped in the nut.

When I get the replacement bits (belts, pulley dishes, nut), I obviously have to install them. So the question is:-

Do I just follow the repair manual / owners handbook on how tight the belts should be or do owners / users of Haflingers have a different value for how much the belts should deflect in the middle of the return run?

Whilst on this part of the vehicle, has any one thought of changing it to run a modern toothed belt system?
Ought to be easy enough to get toothed pulleys of the correct diameter, the correct centres and putting an idler wheel in should not be too difficult. You could even get one with a spring system to give automatic tension.

Thoughts anyone?

John

Hi John,
Regarding your question of conversion to a toothed belt, my response would be why bother? I see no advantage to this and in fact feel it would be a disadvantage if you are considering a tensioning idler as this is an obvious addition of another point of failure (and idlers do fail often). The original system is simple, virtually foolproof and the belts are readily available at many auto parts stores. Just follow the instructions in the manual and all will be fine.
Cheers,
Steve

Received some bits for Lurch's dynastart. Thought it would just be a question of undoing the nut which has stripped threads so can't be that tight. Take off old belts and pulley dishes - put new ones on.

Forgot to mention you have to take off the governor belt first! So first attempt to undo the nut on the governor pulley results in the pulley turning round and the belt staying still.... now what? There is no hole in the pulley or other method of locking it - another design issue in my eyes. Ended up having to use a pair of slip joint pliers to "squeeze" the belt runs together until they were tight enough to lock the pulley so I could undo the nut, quite difficult with only two hands.

Then, how do you get the pulley off? I seem to have lost my 3 legged puller so had to resort to a slide hammer with an "L"arm on it behind the pulley and move that round the edge until it came off. At which point because I was working on a slope and the engine is the lowest end, the oil from inside the governor started pouring out! Quick stick a rag in there to slow it down / stop it.

New belts only just squeeze past the rear engine tin ware to bodywork seal. I seem to have 6 shims and they appear to be paired thickness's, so book says equal shims either side of the centre pulley so I though that as both the belts and pulleys were new I would put them all in use and not put any under the nut. I did the nut up to 70lbf as per the book, (why do they tell you the torque setting in the section about dismantling)?

So now to put the governor pulley back on, what a pain! It has a key / key way and every time I tried to put both the belt and the pulley on the shaft, the shaft would turn! So in the end, I put the belt on the governor pulley, got the key / key way started, put the other end on crank shaft pulley as best as I could and then turned the crank shaft pulley whilst holding the belt in the "V". I know that's not good for the belt, but I couldn't get it to go on any other way. It did go on with out any effort and the governor pulley moved on to the shaft as the belt went into the "V". Same method to do that nut back up as to undo it. Is there a better way?

I think I need some more shims as the belts seem a little tight.

So having had the silencer welded back on to broken pipe and now having sorted the dynastart pulley issue, what's next to break / fall off / require replacing?

John

Hi John,
Sorry to hear that you had trouble with the governor belt but you needn't have removed the governor pulley. Just start the belt over the pulley rim then turn the motor over by hand and the belt pops right off. The same process as installing and removing a bicycle chain. The method will not harm the belt if you work slowly.
I would not worry about the dynastarter belts being a bit tight initially as they will very soon stretch a bit with a little driving. Also note that you may soon find that having an equal number of shims on either side may not be correct as the belts often stretch at different amounts. I also think that you cannot use more than a total of six shims as there will not be a sufficient number of threads remaining on the dynastarter shaft to maintain the proper nut torque.
Cheers,
Steve

Cheers for that Steve, (after I struggled to get the nut off and the pulley).

Actually, that still doesn't address the fact you have no real way to hold the governor pulley should you really need to take it off. Repair manual does not tell you how to take the belt off.

The hand book says to add shims / washers tot he lower mounting bolt of the governor to adjust the belt tension, I wonder if you are supposed to take them out if you are going to take the belt off, put it on? That would make "turning" the belt on or off easier.

Still all done now and as I don't have any more shims I could use, I will drive it as it is! I have booked to go to the "War & Peace" show which is about 60 miles away.

You also have touched on a reason for changing to a toothed belt - being only one, it would stretch but that would be taken up by the idler wheel and you wouldn't have the trial and error of swapping shims around to get the correct tension.
If the conversion was done correctly, it would be totally reversible.

John

Hi John,
I used a nylon strap wrench to hold the pulley when rebuilding one of my governors. You could accomplish the same result using a short length of cotton rope whose diameter is about equal to the pulley width. Make a loose loop around the pulley then tighten the loop by twisting the rope with a wood dowel inserted.
My other two governors could be held by hand so I had no issues with them.
Cheers,
Steve

Hey there,

if you really need to take the governor pulley off, you would most likely want to disassemble the governor (repair or whatever). In this case, you could pull out the whole governor first and then remove the pulley (e.g. by clamping it between woods in a bench vise). Or you could pull out the inwards together with the pulley by loosening the governor's lid.


Regards,
C.

I was pointing out that with the belt in place there is no real way to hold the pulley other than using the belt (which you could damage in doing so).

I would use any / all of the methods suggested if the belt was off. The issue was that I did not want to "pop" the belt over the edge of the pulley as that could / will cause damage to the internal structure of the belt. So I thought it better to take the pulley off.

At least now there is a thread for people to read if they ever need to do theirs, with several options listed from which they can choose.

Thanks to the marvels of the Internet and forums!

John

How do you hold the dynastart pulley while you undo the nut? I have a matched pair of new belts to fit.

You can stop the Dynastart pulley from turning so you can undo the nut by using the hole in the fan blade hub and putting a stout rod / screwdriver in there and locking it against the Dynastart ‘s bearing housing.

There is another thread on here with details of how you tension the new belts.

If you can’t find it, post back on here and I will detail it for you.

John

heinkeljb wrote:There is another thread on here with details of how you tension the new belts.

I think this is the one John is talking about viewtopic.php?f=6&t=3630

John has a post in the thread on how to do it.

Garry

G,,day
the original tool kit has a shaft for the dynastart hole .
i think the diameter of the small end is 8 mm

kerry

Thanks, folks.

Well - so much for my "matched" pair of fan belts!! Currently one is tightish and the other is quite slack. When I fitted the (new) belts in November, I placed the same quantity of spacers between the pulley halves for each belt.

So now I nee to do it all again, but I want to check here what belt specifications that others are using. The parts book says 9.5 by 813 but makes no mention of the profile of the belt. In November 2018, I replaced the existing belts with the same profile and length that was fitted previously - 11A0815.

What belt specs are other using?

Cheers

John W

I have two of these on my engine

http://www.daycoproducts.com/part?categ ... er%3D17330