The Triumph Dolomite Club - Discussion Forum

I am beginning suspect that my gearbox might have a suspect layshaft bearing. The box whines in 1st, 2nd and 3rd under load, but there is no sound in 4th. My guess is this is the curse of the variable part quality we get now, I also have a noisy release bearing on the clutch and that is brand new. How difficult is it to replace that bearing, or would it be best to live with it? If I get another one, is there any guarantee it will be a better bearing?

The car is now idling better after a fix vacumn leak and carb rebuild. However turning the headlights causes the idle to drop from 800 revs to around 600. It is in danger of stalling the car. Now in my homemade wiring I have taken the power feed for the rely setup from the battery. I wondering if taking it off the alternator would reduce the voltage drop from alternator and the load on it?

The trick with the relays is to make the cable runs as short as possible. This is very easy to do with the 1850 & Sprint because the loom for the headlights is run right under where the battery is situated so you can situate the relays next to the battery and the loom which keeps extra wiring as short as possible. The idle shouldn't be affected by having the headlights on. Just make sure your connections to the battery are secure.

Toledo Man wrote:.... The idle shouldn't be affected by having the headlights on. .....

Really? I think it may well have an effect.
38W x 2 for the dip beams, plus sides plus rears plus instruments...maybe 6 to 8 amps at 14V from you alternator, on a car that has no electronics or valves to automatically adjust idle speed?
Maybe there's something wrong with my car too then.

Edin Dundee wrote:Maybe there's something wrong with my car too then.

And every one I've owned too.

I wonder if the idle is affected similarly if you leave the lights off but switch on the heater fan to full + HRW +wipers + brake pedal? A bit tricky to get them all on at in the same instant, but that lot has a reasonable draw to it. If the idle is affected similarly then maybe it is not an issue caused by the headlamps and associated circuit.

Unlilkely.

If its the box you got from me IIRC it had a new laygear pin and bearings from a proper source, having had some bad experiences with the improper source.

Check the oil level PDQ.

Jonners

Jon Tilson wrote:Unlilkely.

If its the box you got from me IIRC it had a new laygear pin and bearings from a proper source, having had some bad experiences with the improper source.

Check the oil level PDQ.

Jonners

The oil level is fine, I have double checked it to make sure. Filled upto the drain plug level, and looked inside with torch.

Basically there is a whine as the revs increase in 1st, 2nd and 3rd, whcih makes me suspect that the bearing may have come from a bad batch. Wouldn't surprise me, my experience with classic car parts is they are a bit of a lucky dip. Some work, others don't. Hence the love for new old stock.

As for the headlight issue, it is working fine on idle with dipped, but mains slows it down. More powerful modern bulbs putting extra load on alternator.

If it idles fine on dipped, I wouldn't worry about it. That's a fair load on an engine with full beam.
I had a new Passat 2L company car around 12 years ago, if the air con cut in just as I was pulling away in the morning the car would very nearly stall, gave me a few frights. And that's with all the modern gizmos.