Escort Sigma 1600 Race Car

[Roger Miller]

Re: Escort Sigma 1600 Race Car

Heres the bearing on a kitchen counter.


Here it is held agaist light.


I believe it should not be letting daylight trough. I don't know the RPM rating for the bearing but it may have been spinned too fast in too hot and the seal gave.

The new ones are rated for 14 000rpms. Adn the tensioner pulley dia is bigger than the cranks cam belt pulley so the it should rev less than the engine.

Whats the number etched into the bearing ?

I would buy a new bearing, but maybe a tighter tolerence unit and pop the seals out and half fill with high temp grease.

Do not use steel seals. Steel seals are for high temp applications, ONLY because the steel seal doesnt melt. U do not have a a high temp [over 120 c ] situation.
High temp bearing will also be higher clearance.
Steel seals will let rubbish into bearing.

[Roadsport]

Re: Escort Sigma 1600 Race Car

Well, an awesome opportunity presented itself to change back to rubber seals as I fucked up pressing the new bearings in place
I believe I'll order another set of bearings tomorrow. Now I'm torn between the two choices though. The rubber seal seemed like it had too much revs and wore down letting the grease out. The metal seal one takes more heat and revs and according to the salesman will not leak the grease out
Well, the ones pressed on place today sure did when I gave the tensioner some revs using a bolt gun. But the again something went wrong with the pressing cause it was very reluctant and stiff to rotate.
Would the dust entering the bearing be an issue if an cam belt cover is used?

[Graham]

Re: Escort Sigma 1600 Race Car

Would the dust entering the bearing be an issue if an cam belt cover is used?

i dont think so, in any case your not looking at something thats going to be in service for 10,000 plus miles are you

[Roadsport]

Re: Escort Sigma 1600 Race Car

i dont think so, in any case your not looking at something thats going to be in service for 10,000 plus miles are you

Oh no I sure am not. I'm so paranoid about these damn tensioners I bet I'll be keeping my eye on this tensioner all the time.
Hoping it would not need to be changed more than annually though.

[RWD fords rule]

Re: Escort Sigma 1600 Race Car

Whichever bearing you choose press in the outer shell, do not touch the inner surface or the seal when pressing it in there, then the bearing/seal will not get damaged
Personally I would replace both of the bearings mid season, with the crank spinning to 9000rpm the tensioner would be spinning quite fast

[Roadsport]

Re: Escort Sigma 1600 Race Car

Surely I need to press on the inner shell when pressing the bearing around / on to the hub ?

[Roger Miller]

Re: Escort Sigma 1600 Race Car

I believe it should not be letting daylight trough. I don't know the RPM rating for the bearing but it may have been spinned too fast in too hot and the seal gave.

.

Bearing clearance would make the seal like that, or maybe its a high temp bearing with rubber seals fitted.

Whats the part number ?

http://www.skf.com/portal/skf/home/products?lang=en&maincatalogue=1&newlink=1_4_7

[Roadsport]

Re: Escort Sigma 1600 Race Car

Good morning Roger.

If I remember correctly the number was 6906RS and the new one was the same but Z on it for steel seal.
The measurements aere 30mm inner dia 47mm outer and 9mm wide.

[Roadsport]

Re: Escort Sigma 1600 Race Car

According to this SKF table the rubber seal one is for 8500rpms and the one with steel seals is for 15000 rpms.
The cam belt pulley on crank is 56mm in diameter and the tensioner pulley is 72mm so even when the engine hits 9000rpms the tensioner should not be spinning at 8500.

http://www.skf.com/skf/productcatalogue/jsp/viewers/productTableViewer.jsp?&tableName=1_1_1&presentationType=3&startnum=15

[Roger Miller]

Re: Escort Sigma 1600 Race Car

2RS = 2 x rubber seal

zz is =2 x steel seals.


But whats the clearance.

did u read the link ?

......................never mind

[Roadsport]

Re: Escort Sigma 1600 Race Car

No idea on the clearances Roger.
I talked to another bearing supplier today. And again he convinced me that the steel seal is worth a try.
I described how the old bearings looked and he figured they have been too hot.
As the rubber seal actually touches the inner shell they have the tendency to run hotter in fast reving applivations than steel selas. The steel dust guard does not actually touch the inner shell so it stays cooler. I was told. And when the cam covers are in place the poor dust protection should not be an issue.
Worth a shot to me. He did point out a possible trerminal flaw in this tensioner design. It uses two ball bearings pressed together which are not meant to be used that way. This may cause the other bearing to take all the load and not share the load between the bearings.

I guess I'll get to know the answer ot that claim too in time.

[RWD fords rule]

Re: Escort Sigma 1600 Race Car

Are the bearigns pressed into the outer shell or pressed onto the inner shaft? what I meant was not to transmit any pressure throught the ball bearings when fitting them, I'm sure you know that anyway, just that you said it was damaged when fitting

Sounds like the bearings with the steel seals and the timing belt cover may be your best option judging by the much higher rpm ratings and what the supplies are saying, sorry if I am pestering you I just don't want to see your engine coming to any harm with all your hard work and time put into the build

I am certainly not an expert but just wanted to offer my concerns, sometimes it is the most simple things that can make the biggest difference

Best of luck with the new engine, I bet you can't wait to get out racing again

[Roadsport]

Re: Escort Sigma 1600 Race Car

No trouble at all! I don't feel like you or no one else are pestering me. I believe the true value of these conversations is to share opinions and experiences.

I'll get the new bearings next week. I decided to take to my local machine shop to get it done propperly this time.

I have not even been thinking of the actual driving .... I'm too busy sorting it all out before the first race.

I feel like theres again a good few things working againsta me soo its going to be close.... again....

Received the new friction plate today. After three weeks wait. And the part was wrong. Luckily it was the retailer who recommended and ordered it for me so he'll propably take it back. I'll have to use the old friction plate now since I don't have time to wait for another. The old one still has a healthy dose of 0,7mm of meat on it still. On both sides though.
Also received the new stainles braided Pro Gold oil hoses from Think Auto this week. I love that company. Their service is outstanding and they always seem to have just what I need.

[Tristan]

Re: Escort Sigma 1600 Race Car

re the clutch.. try http://www.clutch-specialists.co.uk/
spoke to them ,nice people ,and i hear good stuff aboutthem.

[Zetecalex]

Re: Escort Sigma 1600 Race Car

I see you have a slim rear water take off. I was wondering where you bought this from as i need one for my project of putting a 1.4 into a morris minor