Tecumseh vantage 35, very high rpm

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Flowerpots
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Tecumseh vantage 35, very high rpm

Anybody any thoughts, machine was left standing in a garage for 10 years, Obviously wasn’t a starter, after carburettor given a good clean, removed the vanish from Inside. It now starts but the rpm is way to high over 4500 rpm on tac monitor. If you manual close The butterfly with your finger the rpm drops as you would expect and runs fairly sweet. Problem being the governor spring appears to tight and is keeping the butterfly open, tired pushing The steel tab the spring is attached ( left side of carb) to reduce the tension but without much joy. Picture of governor linkage, also tried moving the governor arm towards the carburettor, but again no joy, So any suggestions appreciated.

hortimech
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My first guess would be that

My first guess would be that you haven't reconnected the linkage correctly, but the pictures do not appear, so it is hard to say.

Flowerpots
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Took photos of linkage before

Took photos of linkage before took it apart so they went back same way, try upload photo again.

Chris G
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The link arm looks a bit bent

The link arm looks a bit bent which could be pulling it in. And it could have been placed in the wrong hole to start? 

wristpin
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Vantage information is a bit

Vantage information is a bit thin on the ground but the position of the links appear correct. One illustration does show the Governor spring hooked to the fixed anchor rather than to the Governor arm but the tension will be the same. An outside possibility is that at some point the clamping bolt on the Governor shaft cranked bracket has been interfered with altering the relationship between the internal Governor and the throttle butterfly.

I can’t find any specific instructions for that adjustment but the usual procedure is as follows. Release the clamping bolt, Fully open the throttle and hold it open while turning the cranked bracket as far as possible in the same direction that opens the throttle . Then clamp up the bolt while maintaining the open throttle and cranked bracket position. If I’ve got that right it should give the full range of Governor control.

Flowerpots
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Thanks, we have already done

Thanks, we have already done that suggestion, throttle fully open and cranked bracket pushed as far to throttle. The position of the cranked bracket is shown in the photo it can't be moved any more towards the throttle because the throttle is fully open. Could the internal governor weights be the problem?
The connecting governor spring appears to be to rigid ( although their doesn't appear nothing wrong with it ) and won't allow the throttle butterfly to close. As I mentioned in my original post you can slow the engine manual by moving the cranked bracket away from the carburettor, but as soon as you let it go the spring pulls the throttle to fully open.

wristpin
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If , with the engine running,

If , with the engine running, you push the cranked arm towards full throttle do you get any feeling of resistance or of it trying to close it?  If not, it does suggest an internal problem.

Flowerpots
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Thanks again for reply, the

Thanks again for reply, the throttle at present is fully open ( which you already know) once the engine starts,  the engine is at max rpm due to throttle being fully open, the resistance on the spring is keeping  it fully open. I presume if the internal governor was working it would stretch the spring and move the bracket away from the carburettor to close the throttle and bring the rpm down to a normal speed say under 3000 rpm. Manual you can do this with your finger but as soon as you let go of the bracket, the springs resistance pulls it back to fully open.

Ps it's almost as if it's the wrong way round, you would expect the throttle to be closed when starting and as the engine warms the throttle opens and finds its natural level, but the throttle is fully open to begin with, maybe this is how these carburettors work.

wristpin
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Basically the engine speed is

Basically the engine speed is a balancing act between the pull of the throttle cable ( or fixed anchor) and the opposing pull of the Governor spring. So in the case of your fixed speed engine the “at rest “ position will be an open throttle. As soon as the engine fires the Governor should pull it back against the pull of the spring.

hortimech
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Everything looks correct, but

Everything looks correct, but you say that the governor spring is too tight, just a thought, have you or someone else messed with the governor arm?

By this I mean, was the arm removed from the clamp ? or to put it another way, is the bracket, on the shaft stuck out of the casing, 180 degrees out, this would put the arm further away from where it should be, increasing the spring tension and rendering the governor inoperative.

Flowerpots
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Good point, yes had that

Good point, yes had that thought,  the bracket will turn almost 360 degrees clock wise, so the bracket is on the left of the small governor shaft coming out of the engine, this would make the distance shorter from the spring to the bracket but made no difference. Bracket in position as in photo won't go anymore  anti-clockwise. Apart from taking the engine apart to look at the governor, think we have covered all the reasons it is not playing...

wristpin
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Everything looks correct, but

Everything looks correct, but you say that the governor spring is too tight, just a thought, have you or someone else messed with the governor arm?

That was my thought late (too late!) last night after looking at a Tecumseh service update -  but note that neither example  refers to a Vantage

Then, the only specific reference I could find to a Vantage was in a parts book  - note known to be a 100% accurate assembly guide !

Your reply to H's post

"Good point, yes had that thought,  the bracket will turn almost 360 degrees clock wise, so the bracket is on the left of the small governor shaft coming out of the engine, this would make the distance shorter from the spring to the bracket but made no difference. Bracket in position as in photo won't go anymore  anti-clockwise. Apart from taking the engine apart to look at the governor, think we have covered all the reasons it is not playing..."

If I understand your reply correctly you are interpreting H's comment as swinging the bracket over - that would not work . What I believe he meant was removing the bracket from the shaft and replacing it as per the upper images.

Flowerpots
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That's interesting, looking

That's interesting, looking at the parts book, last photo , it's set up right, because the bracket is to the right of the engine governor shaft, away from the carburettor.I thought if the governor was damaged inside, the bracket would flop anti clockwise , which it doesn't. Anyway another Tecumseh mystery...

hortimech
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If I understand your reply

If I understand your reply correctly you are interpreting H's comment as swinging the bracket over - that would not work . What I believe he meant was removing the bracket from the shaft and replacing it as per the upper images.

Yes it would, but the governor wouldn't.

If you try to remove the bracket, you will probably break it. To prove it is in the wrong orientation is easy, remove the arm from the bracket and try to turn it anti-clockwise, if it turns through 180 degrees, it was in the wrong place, if it doesn't, it wasn't

wristpin
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I agree about the danger of

I agree about the danger of damaging the bracket - hardened steel with “teeth” to grip the shaft.

Probably  time to drop the sump off and inspect the fly weights and bobbin !

wristpin
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The official explaination of

The official explaination of how to reset the governor linkage. Possibly clearer than my effort earlier.

villiers98
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I have had one of these where

I have had one of these where the governor fell apart inside and one Tecumseh on a Suffolk where it appeared to have done ( but did nt take that one apart to see. Time to look inside as suggested