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[TR] Re: Breaking in engine in first gear

To: triumphs-digest@autox.team.net
Subject: [TR] Re: Breaking in engine in first gear
From: Bryan Reese <a241blr63@earthlink.net>
Date: Wed, 18 Oct 2006 20:23:33 -0700
If your TR3 has the original non-synchro first gear DON'T DO IT! You'll 
break the first layshaft gear. I speak from bitter personal experience. 
When I bought my first TR3 in the early '80's, the fellow sold it 
because it had this precise problem.  At that time, junkyard gearboxes 
for these cars were pretty easy to come by. I went through three of 
them, and every single one had the broken first gear. I'd get them home 
and drain the oil and get a hand full of teeth. Finally, my dad took the 
broken gear to a tool and die maker and actually had it repaired. The 
fellow said, "I don't know, that's pretty soft..." It lasted about 6 
months and broke again. I drove that car that way for quite some time 
before I finally coughed up the then-astronomical sum of $100 for a new 
gear and had no further problems (with the gearbox, anyway).

Flash forward to modern times and my current TR3. I'm getting ready to 
pull out of of the local coffee-shop parking lot into traffic, and I let 
out the clutch. Bang! crunch, crunch, crunch... I knew EXACTLY what the 
problem was-- the first layshaft gear had broken. I had just overhauled 
this gearbox myself about six months earlier, and everything looked 
fine. This time the replacement gear was about $250, a lot of cursing 
and a couple of smashed fingers. The new gear said "Made in Italy," but 
oddly, I've had no further trouble

Gears with synchromesh are helical cut, in other words, slanted teeth. 
This makes the gear run quieter, but more importantly, more than one 
tooth is in contact at any given time. Non-synchro gears are straight 
cut, so they are noisy, but only one tooth at a time is in contact. Our 
torquey little TR are engines are sometime too much for them, and of 
course, 1st and reverse have the highest torque of all.

So I beseech you, implore you, go easy in first gear. Keep it under 3000 
rpm, 3500, max. That's all the faster I was going when my gear broke.

As for all this stuff about breaking in the engine itself, gosh, I don't 
know.

Bryan Reese


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