The Lotus Grand Tourers

Here is a picture of the new arrival :


And a nice picture of the cambelt and oil filter :



There were 4 or 5 chunks out of the cambelt like this
Wondering if someone could date the oil filter from this ? The oil was in good condition to be fair, but this looks like it might have been on since the nineties ?

malrig wrote: Wed May 22, 2024 15:01

Yikes!!!

Super thanks to Tony for taking time to visit on Saturday.
Using Stu's Burroughs Gauge (thanks Stu) we were able to check the cambelt, and it is spot on . We also did some measurements on how the gauge works, and comparison with the "Draper/Nielsen" gauge. I have then followed this up with a bit more research, calculation and checks - I'll post some details on that later on the "another timing belt question" chat.
Face to face advice and encouragement is a massive help, and I am now making some progress on the electrics (my least favourite bit).

Cheers,
Malcolm.

You show a photo of chunks taken out of the old cambelt.
My suggestion is that the scrubbers, one above the inlet cam pulley and one on the alternator side of the crank pulley may be too close, loose, or the cambelt has been slack at some point and fouled the scrubber.
With the new belt I suggest you check scrubber gap to the cambelt.
An inspection of the tensioner pulley to ensure no detritus (crap) is on the outer running surface is advised.

Dave the cog.

Thanks for the advice Dave - I will keep an eye on the new belt. I'm pretty sure it's not rubbing on anything at the moment (Tony and I have both watched and listened while it's running up to about 3000rpm).
Clearance to the "scrubber" above the inlet cam pulley is 0.5mm at the closest point - you can just about see in the picture.
I thought this seemed close, but I'm not sure what it should be ?


The old idler pulley is definitely pretty ropey on the surface, so potentially could have been the culprit ?


Cheers,
Malcolm.

More likely the belt picked up a foreign object like a stone. I've just changed my tensioner bearing and the surface looked same as yours but I've never had that sort of belt damage. Has it been running without the upper AND lower stone guards?

The top stone guard is in the boot, which it where it was when I bought the car.
There's no bottom stone guard.
Not sure how long they've been off, but your suggestion is certainly a possibility Pete.
I never really thought about that one as I've run a rally car with a Fiat twin-cam and no cambelt cover for years without issue, but I guess every car is different in the way air flow drags stones and things into the engine bay ?

The 912 upper guard is half the size of the 907 one. The 912, to compensate somewhat, should also have a metal angle iron shaped guard along the lower run from the Exhaust pulley down to the crank pulley. They rust, so may have been discarded on older, higher mileage Excels. If present but misshaped, the lower guard might trap foreign objects too.

Also there should be a plastic rad undertray from the nose intake aperture running up to the oil cooler mount. If that's missing too, then all sorts will get sucked up the front of the engine from the road. And rad cooling won't work so well.

Btw. Rad cooling benefits from the rapid air expansion that occurs once the ram air, squeezed through the small nose inlet, abruptly enters the large space Infront of the rad and decompresses. And if the lower tray is missing, a lot of the decompressed ram air won't go through the rad.

That's helpful info thanks Peter.
The undertray is off at the moment while I'm working on the car, but it looks like it's not been off for a long time.
I think you're suggesting that this piece of metal, which was also in the boot, is the lower cambelt cover ?

malrig wrote: Wed Jun 12, 2024 13:38 That's helpful info thanks Peter.
The undertray is off at the moment while I'm working on the car, but it looks like it's not been off for a long time.
I think you're suggesting that this piece of metal, which was also in the boot, is the lower cambelt cover ?

Looks like it. That said, photo is a bit small but if it were int' boot then make sure it's not the battery retention bracket, just in case! That's another angley thing that gets left off.

That's the battery bracket minus a few bits - is it not?

Yes that photo is indeed the battery bracket.The steel lower belt guard is A010 A011 in the above screenshot.

When staring at it under car A011 (mine's an 89Se) looks like a bit of angle iron but clearly it's more sophisticated than that as seen in the parts diagram. Sorry for the mislead.

Thanks for the clarification guys

Hawaiis0 wrote: Wed Jun 12, 2024 20:38 That's the battery bracket minus a few bits - is it not?

Yep, that’s definately the battery retaining bracket minus it’s two plastic half turn lock inserts.

About time I gave an update on progress, so here goes .....

I'll do it in two goes as there are really two stages to progress (or lack of it) since I last posted.

First stage is up to around mid July :

Thanks to Tony I managed to get the headlamps out so I was able to look at the gubbins inside and think about a fault diagnosis for them not moving
All looked pretty reasonable inside to be fair, including crash panels intact which I understand is a good sign


However, I decided to put off doing work on this and focus on getting out for a test drive.
I was going to just take the car out, but thought it perhaps best to do the steering gaiters first as I already had a pair and it's an easy job right ?
Here started my ups and downs .....
First I found the front wheel nuts were barely more than finger tight ! Good job I didn't take it out for a run.
Then a positive as it looks like the discs and pads are pretty well unused - I suspect they were done a while ago, as they are fairly rusty, but nevertheless, a bit of good news. Also, the front wheel bearings look to have been done.
Ball joints all good with rubber boots intact, except for the top ball joints, so obviously it made sense to do those at the same time as the steering gaiters.
I decided to leave the track rod ends connected to the steering arms to avoid the risk of damaging the rubber boots as they look in decent condition :


The RH track rod and track rod end separated nicely and I went to put on the gaiter - which did not fit !!
The LH track rod absolutely would not play ball - the lock nut was stuck solid.
On the positive side I cleaned up, regreased and rebooted the top joint and that went back together nicely.
I didn't want to separate the RH top joint while I had the steering disconnected, so left that one.

Then followed several weeks of WD40 and repeat tries at separating the LH track rod end lock nut.
I also got busy at work and time ticked away with me feeling a bit down about the car.
On the positive side, I hadn't enjoyed work so much for ages, so I mostly forgot about it, and the poor Lotus sat on axle stands all neglected until October when the story resumes.
I'll post an update of October to present in the next couple of days.

Cheers All and Merry Christmas,