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Timing Belt Covers
scootz - 23/9/10 at 02:16 PM

... who runs their engines without one?

Undoubtedly looks the dogs-danglies, but is there not a high chance of stones flicking up and interfering with the belt-run?

Anyone have any experience of this happening?

blakep82 - 23/9/10 at 02:18 PM

mm perspex
thought about not running mine with one, but stones getting in there doesn't bear thinking about. fine for race cars i think, but not road road cars

SeaBass - 23/9/10 at 02:30 PM

There was a story recently about someone having an engine grenade due to not having a cover and the belt coming adrift.

Personally I'd always run one.

scootz - 23/9/10 at 02:34 PM

Think I just found it James... confirms my thoughts!

Think I'll settle for safety on this one!

whitestu - 23/9/10 at 02:34 PM

I don't have a top cover over the cam pulleys on mine as it won't fit with my alternator belt configuration.

I would have thought the danger is more to do with working on the engine when running rather than stones getting under the belt.

scootz - 23/9/10 at 02:46 PM

I have control over my own destiny when working on a running engine... I don't have control over the engines destiny when running over stones!

ashg - 23/9/10 at 02:59 PM

i havent got one on my pinto but then its only a pinto. have been off in the gravel a few times without any bother. depends what the engine is worth to you at the end of the day

BenB - 23/9/10 at 03:38 PM

I wouldn't consider running without one. It looks fast but broke down on the side of the road doesn't look so good and the covers don't weight that much. Not worth risking it IMHO. Even if it's not great bit stones you'll get shite getting between the belt and the teeth which I suspect might lead to earlier belt failure. Which usually isn't good.

coozer - 23/9/10 at 03:42 PM

I run covers cause I know someone who didn't and got a stone jammed in between the belt and pulley. Not a pretty sight

mcerd1 - 23/9/10 at 03:47 PM

quote:
Originally posted by ashg
i havent got one on my pinto but then its only a pinto. have been off in the gravel a few times without any bother. depends what the engine is worth to you at the end of the day

I've got a pinto too (or it will be once its back together anyway) and I've got its cover all nice and shinny waiting for it

[Edited on 23/9/2010 by mcerd1]

MikeRJ - 23/9/10 at 03:56 PM

quote:
Originally posted by whitestu
I don't have a top cover over the cam pulleys on mine as it won't fit with my alternator belt configuration.


There was discussion about on here this some years ago, and Nat mentioned that if you run without covers, then you need to remove ALL the covers to give stones the best possible chance of escaping. Running with just the top cover removed must be the most risky option available, if a stone does get it it's almost guaranteed to get caught in the belt.

atspeed racing - 23/9/10 at 04:02 PM

There are two trains of thought on this and both these points of view are from top engine builders.
If you run with a cam belt cover then you must make sure it is sealed and they mean sealed up, making sure you put sealant around any gaps and bolt holes.
They also have the opinion that if the stones get in the belt cover it cant get out, if the cover isnt there, it can fall out.
On my own race car I leave the cover off as i can be bothered to seal it up because if I need to check something I cant get the cover off easy.
I did three years in rallycross and never had a belt come off or get any stones damage the belt.
I dont think I have answered any questions, just made more!!
I think whatever you choose will be right or wrong, I think?

coyoteboy - 23/9/10 at 04:08 PM

I've wondered about this for a while and decided that it's either all on or all off. Problem is that the timing marks are indexed on my covers so I can't remove them and then set up the base timing!

mark chandler - 23/9/10 at 05:36 PM

I knew someone that had covers off on his cosworth sierra, buffing the engine with a rag while running......

A few bent valves later not so happy, I would run covers on myself

Werner Van Loock - 23/9/10 at 06:28 PM

I'm running a 4age without covers fine, when i got it, it still had the bottom cover on (with the timing marks), removed that quickly. As mentioned above it's either all on and sealed or none at all.

I've been racing belt driven R/C modelcars for years and it's the same there, fully covered or not at all.

My vote is all off by the way, friend of mine with a zetec powered striker was very lucky once. He was running full covers, but a screw holding the cover to the engine undid itself and got stuck between the belt and one of the cam pulleys, the belt didn't snap but the campulley cracked but didn't get destroyed, so he saved the engine. So covers aren't a guarantee either.

here's a picture showing the left cam pulley spokes broken



And with the 4age i have the benefit of having a non interference engine, so even if it goes wrong, still no bent valves.

[Edited on 23/9/10 by Werner Van Loock]

[Edited on 23/9/10 by Werner Van Loock]

FFTS - 23/9/10 at 08:26 PM

Don't forget that other things can happen where a cover may save your engine. Like the bottom crank sprocket trying to part company with the crank whilst driving. If I had a cover on the belt would have stayed on for the extra mile before I reached home.
See Thread Linky

[Edited on 23/9/10 by FFTS]

zilspeed - 24/9/10 at 09:33 PM

A bloke that botrh Seabass and I know, Ian Longford, races a MK1 Escort with a very expensive Pinto in it.

Ian used to run without a timing belt cover.

Ian visited the gravel at the bottom of Duffus Dip at Knockhill.

Ian wrecked an engine.

Ian now runs a timing belt cover.