Hi guys - I’m new to the MX5 forum. I bought my wife a 1990 Eunos 1.6 just over a year ago. It has 130k km on the clock and is in generally very good condition. I bought it in the winter (ie it was cold) and, given that my wife does not do many miles, I didn’t notice an overheating problem until last summer when it would always overheat when driven more than a few miles. This was first noticed when she came home one day and the water was bubbling away and spilling out of the overflow. She coped for a short while by turning on the heater full blast until I fitted a new radiator from MX5 Parts and all seemed well - no more overheating.
The acceleration and power never seemed that great from when we bought it but I now feel that there must be something that isn’t quite right and I want to diagnose and sort. Another thing to add is that when we start the car from cold and straight away (ie within 10 secs) reverse out of the garage, if we dont give it enough revs and it stalls it will not start again unless left for around 5 minutes. If we start the engine from cold and just leave it for 2 minutes on idle and then start to reverse it will always start again if stalled. Whether this gives any clue to a problem I dont know?
I have cleaned the aftermarket foam air filter and followed the PCM diagnostic check for fault codes and get no flashing lights to indicated a fault ( I had to use an LED across the appropriate terminals in the small diag box just above the air filter). I have just ordered a strobe to check the timing but on looking through the forum I have just read about LWSC syndrome (Light Weight Sports Crankshaft) and I am worried! I have a 4 slot crankshaft pulley with the 4 smaller bolts around the central bolt and I think this means I have a LWSC? The belt was replaced just before we bought the car (according to the paperwork) and I’m wondering whether the pulley was taken off and not replaced correctly, causing the problem as documented in http://www.fizzindi.demon.co.uk/crankshaft.htm.
Can anyone give me advice on what best to check to diagnose this sort of problem. Given the overheating I had also wondered about damage to the head gasket so I was going to do a compression test on the cylinders next. If the timing looks OK and the compression is good does this tend to point to the LWSC problem?
Thanks for any help you can give.
G’day mate, Welcome to the Forum
LWSC the only way to be sure that everything is ok with the pulley is to have it removed and inspect the crank end to see if the slot in the end is worn. If your car has been like this since you purchased it, and the cam belt had been changed just prior, maybe it’s a tooth out