I want to replace my cam belt, any advice?

[MajorMantra]

From detective work in my car's history folder, it appears my 1990 Eunos is probably overdue on time (not miles) for a new cam belt. I'd like to attempt replacement myself and I'd welcome any advice.

Some questions in no particular order

1. I've got the Rod Grainger book and I've looked at various guides online, e.g. this one: https://www.miata.net/garage/timingbelt.html Are there any you'd particularly recommend?

2. I was thinking of going for the full belt-and-braces kits from MX5parts, this one: http://www.mx5parts.co.uk/camshaft-timing-belt-ult... Is this overkill? Does anyone else do a better deal?

3. Is it worth getting some sort of camshaft locking tool to aid in not screwing up the timing?

4. Any other sage advice?

Cheers!

[MajorMantra]

...also, reading around is giving me the fear with regard to the crankshaft pulley bolt and the front crankshaft oil seal.

I've no idea what condition the seal on my engine is in, but given the age of the car I imagine it might need replacing. As it's a 1990, I presume I have the short nose crank.

Soooo... do I change the seal? And if I do, should I attempt the 'Loctite fix'?

(I'm starting to wish I'd never started researching this topic...)

[buzzer]

I would change the seal. I did my cam belt and had to do the seal a few thousand mile afterwards. remember there are two sizes of seal, not sure of the change date. I found it difficult to get the seal in square, and in the end made a tool up to press it in.

The front pulley bolt is very tight, and you really need a tool to hold the crank pulley. its easy to make one out of some steel strip and it makes undoing it, and more importantly tightening it again easy. you will need a torque Wrench.

While you are in there it may be prudent to change the water pump... sod law and all that. EDIT, looks like you have linked to the kit with a pump in it...

I would also definitely use a new genuine Mazda cam cover gasket, or failing that, re use the old one. I have seen three after market cam cover seals leak now, and the leak has been at the front of the engine where its hard to spot. However, I have no experience of the ones from the link you gave, they may be OK.

If you also change the cam seals, Mark the cam wheels as to which side they came off, just makes assembly easier.

the actual timing of the engine is very easy, just align the marks up, I didn't have a need for a locking tool.

there is a picture of the tool for holding the front pulley, and pushing the seal in on my web page.

https://jtccc.wordpress.com/our-cars/about/

Edited by buzzer on Saturday 11th March 18:11

[Sad Weevil]

On a car as old as yours, I'd suggest replacing the cam seals as well as the crank seal. There is a good cam locking tool available from Jass Performance, particularly useful if you're replacing the cam seals:, saves time too.
http://www.jassperformance.com/shop/mazda-mx5/Engi...

[anonymous-user]

Replacing the cam belt on a mk1 is really very easy to do, so long as you buy or make a tool to lock the crank pulley.
Something like this:

http://i.ebayimg.com/images/i/401108446315-0-1/s-l...

I made the equivalent from an old piece of 5mm aluminium but you can use almost anything solid enough, eg:

https://www.miata.net/garage/images/crankshaft_too...

Once you have the crank pulley locked you'll probably just need a breaker bar to under the bolt.
Also, go through this article and check what sort of crankshaft you're likely to have, as you may want to replace the crank bolt too and check on the state of the keyway in the crankshaft if your car has one of the type prone to wear, which I think is likely if its an earlier 1990ish model.

https://www.miata.net/garage/crankshaft.html

Also, I've never used any form of camshaft locking tool (remember you can't use the camshafts to lock the engine to undo the crank pulley as you'll probably break something badly, you must lock the crank itself).

The marks on the camshaft pulleys are very clear so it's easy to set them to the right position, and typically I make white paint marks on the existing belt and pulleys and then count the teeth on the belt from the various marks so that I know exactly how many teeth should be on each run of the belt, then just make the new one match.

Ideally you will check the timing afterwards with the engine warm and running using a timing strobe light, and adjust the position sensor on the top rear of the camshafts to get it spot on to 10 degrees (or up to 14 degrees if you want a more torquey feel to the engine, my 1992 1.6 felt best at around 12 IIRC).

Timing light:
https://www.machinemart.co.uk/p/gunson-g4113-times...

14 degree mod:
http://www.mx5nutz.com/forum/index.php?showtopic=1...
https://forum.combustionpunks.co.uk/t/mx5-eunos-mi...

Edited by anonymous-user on Sunday 12th March 09:56