Triumph Dolomite Sprint

[geoffjimbo]

Just having issues with the harmonic balancer pulley on the crankshaft is there a difference in depth between an 1850 part number 217535 and a sprint part number 217587 as I am unable to line up the 3 pulleys I am suspecting that I could have installed the wrong crankshaft pulley. Any help would be appreciated
Regards Geoff

[dursley92]

Picture of a Sprint pulley compared to a 1850/TR7, you can see its a lot shorter presumably because of the twin row chain sprocket.

[GrahamFountain]

Aren't the timing marks set at different angles to the keyway as well. As I remember, the plates that mount on the block are different between the TR7 and the Sprint, so the mark on the pulley is too.
I think the TR7 Sprint had a standard TR7 one to match the TR7 fan, alternator mounting brackets, and TR7 timing plate.
Graham

[dursley92]

Not sure I understand what you mean about the mounting plates Graham, could you explain more please?

My picture is just a Dolomite Sprint pulley compared to a normal 8valve TR7/1850 pulley to show the different lengths that Geoff was asking about.
You can also see the wear marks from the lip seal on both which shows how far they stick out from the engines for reference.
The rest of the bottom end, like the cranks etc, is common to both engines so the Sprint pulley needs to be shorter to line up with the alternator and fan idler.

I know the Sprint timing cover is deeper than the 8valve one clear the twin row chain.
The little bracket/plate with the timing marks that screws on the front of the cover is different as well.
I have never compared how the timing notch on the pulley is positioned compared to the woodruff keyway on them. That sounds like something to look at tomorrow for interest.

[new to this]

You said it had three pulleys,that doesn't sound like a sprint pulley,my sprint only has one pulleys stag has three pulleys

Dave

[mahony]

You said it had three pulleys,that doesn't sound like a sprint pulley,my sprint only has one pulleys stag has three pulleys

Dave

The three pulleys being the crank the alternator and the fan i assume

[geoffjimbo]

Hi Russ

Thanks for the picture I am guessing the Sprint pulley is 9.5mm shorter than the 1850 as this is the difference in the height of the timing covers for each motor

Regards Geoff

[soe8m]

I alway's found that an ideal situation. Machining an 1850 pulley to sprint size. A nice clean surface for the seal.

Jeroen

[dursley92]

I alway's found that an ideal situation. Machining an 1850 pulley to sprint size. A nice clean surface for the seal.

Jeroen

That sounds an excellent idea, but after Graham's comment I just compared the timing marks of an 8v pulley with a Sprint one and they are completely different. I couldn't dig out an 8v timing cover to compare them at the moment but it must be more than just the depth so I think Graham is correct.
Graham - Apologies for doubting you!

Jeroen - Do you make your own new timing mark?

[soe8m]

I always make a new mark because most of the time they are off. But when they are way off the pulley can be bad. I have seen many of this type where the vulcanisation is gone and the rubber not attached anymore making the outer part can turn around the centre.

Jeroen

[GrahamFountain]

I always make a new mark because most of the time they are off. But when they are way off the pulley can be bad. I have seen many of this type where the vulcanisation is gone and the rubber not attached anymore making the outer part can turn around the centre.

Jeroen

I've heard of that problem, though not seen it.

The plate I was on about is the saw toothed one screwed to the block with the advance and retard angles marked on it. The TR7 and the sprint have different ones (I assume) because the alternator mountings are different and you're looking at the pulley from a different angle. So the marks on the pulleys are, even when they are right, at different angles to the keyway.
I either didn't know or had forgotten that they have different length bosses though.
Graham

[GrahamFountain]

Do I mean screwed to the timing cover not to the block?
Graham