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Re: Starter Problems

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Webb Sledge

Webb Sledge

Jedi Warrior
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Re: Starter Problems

I took the starter off today and took some pictures for opinions. None of the wear on any of the gears looked excessive. Of course there is going to be some wear just from use, but nothing looked to be worn down to the point of failing to engage, as I checked the starter gear and around the entire ring gear. Here are a few pictures:

Ring gear looked like this all the way around:
https://img107.exs.cx/img107/5023/10000051yd.jpg

Someone mentioned that perhaps the battery was "over-engaging." I have an Interstate battery in the car, and I'm not sure if that would cause the problem or not.
Probably the most worn spot on the ring gear:
https://img107.exs.cx/img107/4458/10000094tj.jpg

The starter gear:
https://img107.exs.cx/img107/2087/10000080fb.jpg
 
Re: Starter Problems

Webb, I think you answered your own question. Worn, badly.

Bill
 
Re: Starter Problems

No Bill, neither the starter or the ring gear are worn badly. Naturally, they have wear, just like any starter/ring gear, but that's normally and definitely not enough to cause not to engage.
 
Re: Starter Problems

Web... I'll throw in my opinion (for what it's worth). You definitely have some wear there, but I agree that it doesn't look like it's enough to keep the thing from engaging properly (in my humble opinion anyway). But... I don't have a lot of experience gauging wear on ring gears and starter gears. I will say that you have significantly more wear on your ring gear than I recall having on the ring gear of my TR4. Also, I just looked at the ring gear on my Sprite, and it shows less wear than what yours is showing.

What's the guy you work for (Joe, right?) think about it?
 
Re: Starter Problems

Hello Webb,
you have the ring gear on back to front. There should be a chamfer on each tooth. It should look like the teeth on the pinion. If you feel the ring gear at the back (facing the gearbox), you will feel the chamfer I'm talking about.

I'm afraid it is a gearbox off job to rectify.

Alec
 
Re: Starter Problems

You sure piman? I felt the back and it did not feel any different than the front. Hmmmm. And if that's the case, why did it start fine for many years? It only started doing this about 5 months ago.
 
Re: Starter Problems

Hi Webb,
It's not clear from the photos which type starter you have.

The TR6 originally had the positive engagement type starter. A solenoid mounted on the starter pulls the starter pinion into engagement with the front of the flywheel teeth. The FRONT of these teeth would be beveled & show wear.

The TR2-4 had a "Bendix" type drive. This has no engaging solenoid & relies on inertia to move the starter pinion into engagement, against a weak spring, on a spiral groove. This type of starter engages from the back side of the ring gear & the BACK of the teeth would be beveled.

In any event, the teeth may be burred enough to prevent engagement OR, the starter pinion engaging mechanism, either Bendix or soleniod engaged, may not be traveling far enough to fully engage the flywheel. Your gear doesn't appear to be worn enough to prevent engagement unless the pinion isn't travelling far enough to fully engage.

You might want to clean up the burrs on the two gears & measure the engagement depth to get a better picture of what is happening. There are a couple of reasons for the Bendix type to not fully engage. Mismatched parts would be the only reason for the positive engagement type to not engage.

It's possible that through bad design or wrong parts, the flywheel to pinion engagement is only partial & there is enough wear in your parts to make it fail.
D
 
Re: Starter Problems

The starter is the positive type, it engages from the front of the flywheel. However, from my vantage point, it looks as if the front of the teeth on the ring gear are beveled, and they are showing wear, so I assume all is well in that department. I think it must have something to do with the solenoid, given that this thing worked for years up until recently. We didn't take the ring gear off during the rebuild, and the same starter was reused, so it's not like it got flipped around in that process.
 
Re: Starter Problems

Dont forget that the wear on the arm that pushes the gear out to the flywheel can be CRITICAL too.I would try another starter,they go cheap at swap meets.
MD(mad dog)
 
Re: Starter Problems

Webb, I agree with Dave. Look at the teeth on your ring gear. All the shiny stuff is at the leading edge and on your starter pinion it looks like the mating surface has the same wear. Your starter isn't engaging adequately and only now has the wear become enough to fail. If a new solenoid is cheap and you feel like making the diagnosis go for it. A new or rebuilt starter will provbably be your quick answer.
Cheers! MLA
 
Re: Starter Problems

Hello Webb,
I am certain as to what it should look like. The tooth profile of the ring gear is the same as the pinion profile and your photograph clearly shows that bevel on the pinion (and thatis is a pre-engaged starter). If you can't feel it, try using a small mirror to view.
I can't comment as to why it worked for so many years, but it is wrong. You could use an inertia starter as a stop gap but you will need to add a starter solenoid and a relay if you have a ballast resistor coil.

Alec
 
Re: Starter Problems

Hi Alec,
I don't understand. We don't seem to be on the same page. I "think" the photos clearly show the bevel on the front side where it should be for his type of starter. Are you saying that the front bevel is incorrect & that the real bevel is on the back side? That the front should not be beveled or what?

I'm not sure what you mean by a "pre engaged starter". There are positive engagement types & Bendix (inertia) engaged types. What is pre engaged?

BTW, I converted my Bendix starter, engages from the back, to a positive engagement starter (gear reduction) which now engages the front non beveled side of the ring gear. Absolutely no problems. Perfect engagement & starting every time. I think either the starter pinion or the ring gear being beveled is sufficient.
D
 
Re: Starter Problems

Hello Dave,
I can't have explained too well, the starter picture shows 45 degree lead on the front of the pinion, which travels away from the starter motor body to engage which is correct (Pre - enegaged is the name by which these starters are known in the UK as the pinion engages then the motor is energised.)
The Triumph engine, and others that I have worked on, have a similar 45 degree chamfer on the ring gear. This faces to the front for a pre-engaged and to the rear for an inertia starter. I can believe that it worked without but that does not mean that it is right.
There may well be another problem and what I would look at is to measure the throw of the pinion and the distance from the engine backplate to the ring gear. However, the ring gear is installed wrongly.

Alec
 
Re: Starter Problems

Actually, I talked with the guys at Blue Sky Radiator & Electrical in Harrisonburg and with Joe, and both of them are convinced that the starter and solenoid themselves are fine. Even the ring gear is on in the right direction, and there isn't a 45 degree bevel on the other side, I've checked. What has happened is that the ring gear has slid backwards on the flywheel over the years, and when the starter does engage, it's only by like 1/4 inch or less, when it should be about 1/2 inch or more. Basically I'll have to pull the engine or tranny, probably the latter because it's less work. Needless to say I'm wizzed... to the max. A lot of work wasted for me.
 
Re: Starter Problems

[ QUOTE ]

The Triumph engine, and others that I have worked on, have a similar 45 degree chamfer on the ring gear. This faces to the front for a pre-engaged and to the rear for an inertia starter.
However, the ring gear is installed wrongly.
Alec

[/ QUOTE ]
Hi Alec,
From the pictures, it appears to me that the chamfer IS on the front side as it should be. Why do you say that it is on the back? Do we have a photo interpretation problem, or am I just blind?

Webb,
Consider spot arc welding the ring gear onto the flywheel in about four small spots. I have seen factory assemblies that were spot welded. Keep them small & evenly spaced to not disturb flywheel balance. Or, rebalance the assembly after welding if you are nervous about this sort of thing. The welds can easily be cut if the ring needs replacing.
D
 
Re: Starter Problems

Hello Dave\Webb,
please look again at picture one, the tip of each tooth is rounded due to the starter pinion engaging. This is not the chamfer that is machined originally. Look closely at picture three of the pinion, the chamfer is 45 degrees across the tip from crown to root, that is what should be on the front of the ring gear also.
If, as you say Webb, there is no chamfer either side then I don't know where that gear came from, but as I keep saying it is wrong. I think that there were two points from your earlier post on this, one was that the ring gear can move on the flywheel and that Triumph actually fitted the ring gear incorrectly due to the transition from inertia to pre-engaged starter.

Webb, I can understand that you are upset at the thought of removing the gearbox, so you may like to consider a temporary fix of either using a slide hammer with 90 degree 'claw' to drag the ring gear back home, or fabricate a screw puller to pull it back onto the shoulder. A few tack welds as Dave suggests may even make it a longer 'quick fix'

Alec
 
Re: Starter Problems

Hello Dave, Webb,

I tried to find a photo to show you but couldn't find one.
I have doctored your picture, Webb to try and illustrate what I mean.

Alec
 

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Re: Starter Problems

[ QUOTE ]
Hello Dave, Webb,

I tried to find a photo to show you but couldn't find one.
I have doctored your picture, Webb to try and illustrate what I mean.
Alec

[/ QUOTE ]
Thank you Alec. In view of the somewhat "damaged" nature of the present ring gear, I personally would install a new ring gear in the correct position & spot weld it to the flywheel. This would be pretty much a permanent cure for the problems. It appears that TR ring gears have the setback problem more often than some other cars.
D
 
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