- My model of MX-5 is: __NB
- I’m based near: _Hastings
_
- I’m looking for technical help or recommendations on: _Setting valve clearances
_Has anyone used another tool, apart from the MX5OC one, to get the valve shims off a NB engine?
I asked to borrow the Club valve-locking tool in May so I could get the shims off the engine of my NB to measure them and get replacements. Unfortunately, Royal Mail were unable to deliver the tool but a card wasn’t put through the letter box telling me about the attempted delivery and the Club Office didn’t tell me they had sent the tool, so I couldn’t go to the local Sorting Office to collect it. After 18 days it was returned it to the Club Office.
I suggested a courier be used instead to get the tool to me but have heard nothing since.
I’ve been notified today that the MoT expires in a month and have told the garage that the car is still off the road and will not be ready in time.
There are several tools listed online for this job. Will any of them fit the NB 1.6 engine?
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This is interesting.
Is yours the later VVT head?
We have an NB FL at 106,000 miles, with zero top end chatter.
It’s in the service book to do I think, but in our 15 years I’ve never once heard of it being actioned on any forum.
Hi Tom. I am interested in the technique for doing this job as the clearances on half of the valves in my 1.8 are not to spec.
If you can add any links or elaborate, ideally with pics, on how you do the job I’d appreciate it.
I’m procrastinating as it looks a bit tricky.
Cheers,
Guy
This is something I have been wondering about but never seem mentioned on here before. From my experience of motorcycle engines if anything over time the valve clearances tend to close up so you don’t end up with a rattle but burned out valves instead because of tight adjustment holding the valves slightly open if severely neglected. Of course bike engines are much higher revving & built to tighter tolerances than a car one. I found that once the initial bedding in & adjustment had been done at around 15k then they stayed within tolerance pretty much forever after that.
I think the op has a 1.6 & they never had the vvt.
Hi Phoenix, that’s what I’ve found.
This would mean replacing some shims with slightly thinner ones.
Hi,
My car is a base model 1.6 which has done just over 81000 miles. My Haynes manual says to check the valve clearances at 70,000, but the previous owner may not have bothered. I have a micrometer and pick-up tool. I’m just waiting for the valve-locking tool from the Club Store to arrive again.
Have you measured the clearances? You can do that without the need for the tool.
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Yes, I did that in May. My American Haynes manual specifies an inlet valve clearance of 8 to 9 ‘thou’ ( 0.2 to 0.23 mm ) and an exhaust valve clearance of 12 to 13 ‘thou’ ( 0.3 to 0.33 mm ). It states the engine must be at top-dead centre with No. 1 cylinder on the compression stroke, but this confused me as the cams for No. 1 cylinder were not completely in the ‘dwell’ position. As the diagram in the manual seems to have inlet and exhaust valves mislabelled or the engine shown back-to-front, I decided to ignore the manual and measure the clearance between the base of the cam and the ‘bucket’ with the cam lobe pointing directly away from the bucket. I worked my way through the valves from No. 1 cylinder to No. 4, turning the engine before measuring the clearances for the next cylinder in the sequence.
The results range from 6 to 10 ‘thou’ for the inlet valves and 10 to 13 ‘thou’ for the exhaust valves. As the variation allowed is 1 ‘thou’ according to the Haynes manual, it looks like I shall have to fit new shims to some of the valve buckets.
This is the first time I have worked on an overhead cam engine, but I used to do this job on the pushrod engines in my MGB and Skoda Estelle in the 1990s.
Richard Axe
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Did the B not have ring spanner and slot head tappets??