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View Full Version : TR6 Starter & Clutch Problem (72 TR6)



Webb Sledge
09-21-2004, 08:11 PM
Sometimes when I go to start my car the starter will just grind against the flywheel, instead of engaging completely. This doesn't always happen, but will sometimes, and rarely it will do it a second time after I've flipped the key to off, waited for it to stop spinning, and then try to crank again. I think it needs a new relay or starter. What do you think?

Also, sometimes when I go to put it in reverse, the gears will grind, even with the clutch as far as it will go (ie, to the firewall). This is embarrasing, but moreso it's bad for the gears. Could it be the throwout bearing that's sqealing again? The bearing needs to be replaced regardless of the gear problem. Suggestions?

Geo Hahn
09-21-2004, 09:02 PM
I would suspect the starter rather than the relay as I think a relay/solenoid failure would not partially engage. May just need a cleaning up. Don't know if TR6s use shims to adjust the starter, if so these are sometimes omitted and can cause poor engagement.

As for grinding going into reverse -- sounds like the clutch doesn't fully disengage. Would start by bleeding that guy though it could be the dreaded broken clutch fork pin. If you are going to replace the TO bearing it would be an ideal time to tackle that pin if it is broken.

Sorry - had a great link (Buckeye Triumphs) on the fork pin but it seems to be 404 at the moment.

big6
09-22-2004, 08:57 AM
Have you checked the end float of the crankshaft? It could be that your crankshaft thrust washers are damaged. When you shift into revese, try pumping your clutch pedal a few times and see if it goes into reverse without griding. If the crankshaft moves to the rear the starter drive gear can be too far away to fully engage a warn edge of the flywheel ring gear. Thrust washer wear is a common triumph problem with TR6's and 1500 spits.

When starting a triumph or most british cars, the transmission should be in neutral and the clutch pedal out. The triumph engine with the stock oil filter delays the engine developing inital oil pressure at starting. With the clutch pedal pushed in the while starting the engine, the thrust washer has pressure applied without the benifit of lubrication. Also, when setting at a traffic red light it is a good practice to shift the transmission into neutral. Leaving the pedal pushed in at idle will also cause premature wear of the thrust washer.

Terry

Rick O.
09-22-2004, 09:31 AM
big6 is on to a good one. Another indication of worn TW's is a drop in idle RPM when you mash the clutch (extra friction due to forcing the crank against all the journals). There shouldn't be more than a fingernails' width of endfloat (0.006 inches). A quite doable garage repair that I tackled last winter.

Webb Sledge
09-22-2004, 06:09 PM
It's definitly not the thrust bearing, though that was a good guess. I thought it might have been too when you said that, but I just went to check and it stays right between 1150 and 1200 rpm at idle, with it in or out. My engine needs a rebuild badly, which I gonna happen in 3 or 4 weeks. Right now it's missing pretty badly on at least 1 cylinder, and the idle RPM has to be kept up fairly high (>1000rpm) to keep it running smoothly.

Eric
09-22-2004, 06:43 PM
I don't know about TR6s specifically, but often if you shift into 2nd before shifting into reverse, you'll get less graunch.

BRIAN TOWNE
09-22-2004, 07:03 PM
Webb
As Eric says, I always go into second before reverse. Just becomes habit. The high rev's will not help matters either.
Any clicks or clunks going into other gears? How high off the floor does the clutch engage? Perhaps a slight adjustment is needed.
Brian /ubbthreads/images/graemlins/canpatriot.GIF

Kurtis
09-22-2004, 10:25 PM
Webb,

Your engine may very well need a rebuild; however, be sure to check all less expensive remedies before plowing into a full rebuild. The symptoms you describe could be easily be caused by worn carburetors, or a simple electrical problem (bad plug, bad plug wire, etc.).

Try spraying some carb cleaner around the throttle shafts of your carburetors while it's idling. If there's any change in RPM's, worn throttle shafts on your carburetors are the likely cause of your idling problems.

Webb Sledge
09-22-2004, 10:35 PM
No, my problem isn't only a missing cylinder. There are many other things wrong as well, which I knew when I bought the car. It burns oil (needs new rings), smokes on start up (bad valve guides), and the oil pressure would be reading very low if it were not for the oil pressure relief valve trick, where you rig it up with a screw to show good pressure on the gauge. The crank and cam also need a regring. Plus I'm junking the Strombergs altogether and putting twin Webers on.

Brian, the clutch goes all the way to the floor, there might be a cm there between the pedal and the firewall, I haven't checked, but it goes down quite a ways down.

CDNMGBguy
09-23-2004, 05:25 AM
Start by having your clutch hydraulics checked. If they are bagged then you will have these problems. In the event the hydraulics check out ok, or problems continue after the sorting of the hydraulics. Then . . . it is most likely your release bearing. Been there done that. Does the car sometimes take up the clutch in an unpredictable manner, and other times refuse or be a tough shifter into 1st gear - then suspect the release bearing. If it needs replacement then replace all your clutch bits at the same time.

piman
09-23-2004, 07:41 AM
Hello Webb,
it is a common Triumph trait that the starter occaisionally fails to engage and just screeches. Mine does it about every other month, (Used everyday)
Also, the high idle speed will make it difficult to get a clean engagement into reverse, 6 to 700 rpm is what it should be.
May I suggest that you fit twin HS6 S.U.'s rather than Webers, unless you plan substantial power modifications when three Webers will give a moderate power advantage at the top end.
regards,
Alec

Webb Sledge
09-23-2004, 05:49 PM
Yes, the transmission is sometimes nearly impossible to put into first gear, and I KNOW for a fact that the release bearing needs replacing, so that's a very probably cause.

When you start your car, do you have to time letting go of the key just right? because if I hold the key for 1 split second to long after the engine is turning on it's own power, it will grind until I let go.

MDCanaday
09-23-2004, 09:58 PM
You will need a new ring gear also, your's has the teeth worn badly in one place due to old age and use. The 6 starter is super strong, good used ones are cheap as a result.
MD(mad dog)

trrdster2000
09-23-2004, 10:16 PM
Joe, sounds like you have a full plate of repairs to do , just make sure to check your starter bendix and ring gear on the fly wheel, one or the other or both would seem to be the problem with the starter. Funny thing about engines, because of the balance of all the moving parts, they almost always come to rest in the same place, thus, wearing out the same gears on the flywheel.

Dave Russell
09-23-2004, 10:28 PM
[ QUOTE ]
and the oil pressure would be reading very low if it were not for the oil pressure relief valve trick, where you rig it up with a screw to show good pressure on the gauge.

[/ QUOTE ]
I'm not so sure about this. As far as I know, the pressure on the gage is the same as the pressure in the engine. The relief valve is either partially open when the available pump pressure exceeds the spring setting or it is closed. It's opening is controlled by a fixed spring rate. If the pressure at a given rpm & engine temp comes up when the spring is shimmed it simply means that the spring has lost some of it's tension & is releasing at a lower pressure than it should.

If a worn engine were the cause of the low pressure, shimming the relief valve would not help because it wouldn't be opening in the first place. Loose bearings or a worn oil pump would be letting the pressure out before the valve reached it's opening setting.
D