Jackshaft rotational play

[MLCstag]

I'm about to remove the jackshaft sprocket whilst replacing the timing chains etc but have noticed some rotational play in the jackshaft.

The play is about 2mm during which the distributor rotor arm does not move. This doesn't look right to me but could be normal for stags? When the engine is turning the play would be taken up so I'm hoping this is normal.

I will be taking my water pump out for inspection so was wondering if the jackshaft should be removed and inspected. Of course prefer not to disturb unless really necessary.

[staginhiding]

You will be able to see the teeth on the jackshaft if you remove the water pump.
You need to look at both the pump and jackshaft teeth for wear as it sounds like this is where your play is probably coming from.

Post a pic on here if you are unsure about how much wear is acceptable..

Hope that helps

Sam

[V Mad]

2mm on the full diamteter of the sprocket doesnt sound like a lot to me.

[staginhiding]

Agreed,but its always worth just checking as this is a weak point for the engine..

[MLCstag]

Agreed,but its always worth just checking as this is a weak point for the engine..

This is concerning me and do want to inspect the water pump teeth. What about the distributor gearing as that's where the play is showing up.

thanks Brian

[staginhiding]

Brian
I think if you are concerned and for your peace of mind it would be worth you looking at the gear on the distributor and rod that then runs from it on to the oil pump..
It doesnt take long to take the distributor and jackshaft out as you are doing the chains anyway.
That would mean you will have checked everything that is causing you concern,renew as required and fit it all back with confidence..

But bear in mind as Chris says that is a long run not to have a bit of movement..

Others might think differently..

Sam

[staginhiding]

Brian

just a thought,it isn't just the sprocket moving on the dowelss to the jackshaft...

[MLCstag]

Brian

just a thought,it isn't just the sprocket moving on the dowelss to the jackshaft...

Thanks Sam
I will check that again tomorrow but believe I witnessed the shaft moving ( my timing marks). Have just been looking at the process for removing distributor and it looks straightforward enough. The problem as ever will be deciding what's acceptable wear and play.

Hopefully get a few more views before I replace anything along the way.

[staginhiding]

Brian,just come back on when you need help,there are plenty of people on here who are willing to give good advice..

Its probably all ok as that 2mm could probably be just in teeth meshing..but as always you need to feel confident when its all back together that you havent missed or not done something..

Sam

[StagnJag]

I don't think I have ever heard of distributor jackshaft teeth stripping (I could be wrong though). The place that would certainly be worth checking is the free play between the Jackshaft and the water pump.

Regards

Dave

[flying farmer]

The distributor drive teeth do wear on the jackshaft, but don't normally fail catastrophically like the water pump teeth.

I have had to replace the jackshaft on my project Stags engine due to wear on the distributor drive teeth, the water pump teeth were perfect, just like on the spare jackshaft I have got that I took out of a scrap engine.

Neil

[V Mad]

I notice that wear on the distributor pinion is usually moderate, but sometimes more than you would like. Obviously high mileage and maintenance is a factor but I wonder how quickly they wear when one of these aftermarket 'high pressure' oil pumps is fitted.

[Staghound]

I am doing a complet engine rebuild, should The jack shaft be new or will the original 60,000 mile one do? It looks to have only light ware on the teeth...

Andrew.

[staginhiding]

Hi Andrew

Personally I would stick with a genuine one with only light wear...pleased to see things are progressing for you..

Sam

[pitzey]

Hi Stagnjag, i have a stag and jag also