I have one of these, but I am not all that sure I can use it!Alan_M wrote: ↑Sat Oct 21, 2023 21:55They may not be available new, but often come up for sale on EBay etc. You’re most likely to find the generic BT-33-73f gauge. This is the same as the Lotus one, except for the dial scale shows figures, rather than the single mark shown on the Lotus one. The calibration can easily be checked.
Another timing belt question
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Re: Another timing belt question
Of all the things I have lost I think I miss my mind the most...
1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel
1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel
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Re: Another timing belt question
Why?Zaphod wrote: ↑Wed Feb 07, 2024 11:58I have one of these, but I am not all that sure I can use it!Alan_M wrote: ↑Sat Oct 21, 2023 21:55They may not be available new, but often come up for sale on EBay etc. You’re most likely to find the generic BT-33-73f gauge. This is the same as the Lotus one, except for the dial scale shows figures, rather than the single mark shown on the Lotus one. The calibration can easily be checked.
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Re: Another timing belt question
I have a horrid noise that I though was a failing tensioner, but having changed it it’s still there, the short of noise that might be an over tight belt.. the guage reads just over 90 when cold
Of all the things I have lost I think I miss my mind the most...
1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel
1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel
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Re: Another timing belt question
Have you removed the ancillary v belts to listen without them?
Nothing is fool proof. Fools are clever!
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Re: Another timing belt question
Ive never faffed around with gauges using the twist method instead, but, if its too tight it sounds high pitched, if its too slack it sounds slappy. Not very scientific I know but.....
Bash
Bash
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Re: Another timing belt question
I use an Krikit gauge - much cheaper and widely available.
The ever reliable and thorough Tim Engel did a comparison, posted on this post on Pistonheads, you need about ~52 on the Krikit scale.
The ever reliable and thorough Tim Engel did a comparison, posted on this post on Pistonheads, you need about ~52 on the Krikit scale.
"Farmer" Richard
1990 Lotus Excel SE (Lilith)
2022 MG MG5 EV (not due to be a classic for quite a few years...)
2011 Nissan Leaf (Ragly - EV pioneer, must be due to be a classic one day)
1990 Lotus Excel SE (Lilith)
2022 MG MG5 EV (not due to be a classic for quite a few years...)
2011 Nissan Leaf (Ragly - EV pioneer, must be due to be a classic one day)
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Re: Another timing belt question
Yes, and the horrid noise is still there!
Of all the things I have lost I think I miss my mind the most...
1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel
1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel
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Re: Another timing belt question
I printed off Tims advice regarding Cam belt tension many years ago and still refference it today. But if you can accurately gauge 52 on the Kri-kit scale you are a better man than me. Good news is that you don't have to be spot on accurate - do your best to get 52 but slightly off is OK in my experience.rbgosling wrote: ↑Thu Feb 22, 2024 12:11I use an Krikit gauge - much cheaper and widely available.
The ever reliable and thorough Tim Engel did a comparison, posted on this post on Pistonheads, you need about ~52 on the Krikit scale.
Cheers, Phil
Never take life seriously, nobody gets out alive anyway!
Never take life seriously, nobody gets out alive anyway!
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Re: Another timing belt question
This is a new question, but the subject is still valid, so I've put it on here.
I have just changed the cambelt and idler pulley on my 1984 Excel (square tooth).
It all seems ok based on a twist test and the sound now it's running. I reset the auto tensioner to the same position as the old belt, but that was in a pretty poorly state.
I'd now like to check the tension properly and provide a proper reading on the Draper/Laser/Neilsen gauge for people to use in future, hopefully with a bit of science and reassurance to give people confidence.
Hence I'd like to borrow a burroughs gauge, or alternatively visit someone and check their properly tensioned belt with the Draper tool ? Maybe someone could bring their car and tool to Weedon on 25th May if the meet is on ? (I'm in Milton Keynes by the way).
I suspect the 15 over 13 reading shown in Mike C73's blog is about right, but I was then confused by his reference to making the scales coincide at 17, hence my desire to double check. I currently have mine set a bit tighter than that, so I'd like to do the check before running the engine too much more.
Also, I forgot to check the size of the auto-tensioner locknut when I had it apart, and now it's all covered with v-belts etc so I can't get a vernier on it.
I don't really want to strip all the v-belts off again and I think I would be able to get to it with a suitable ring spanner if I had one the right size - if someone could let me know the size it would be much appreciated.
Many Thanks,
Malcolm
I have just changed the cambelt and idler pulley on my 1984 Excel (square tooth).
It all seems ok based on a twist test and the sound now it's running. I reset the auto tensioner to the same position as the old belt, but that was in a pretty poorly state.
I'd now like to check the tension properly and provide a proper reading on the Draper/Laser/Neilsen gauge for people to use in future, hopefully with a bit of science and reassurance to give people confidence.
Hence I'd like to borrow a burroughs gauge, or alternatively visit someone and check their properly tensioned belt with the Draper tool ? Maybe someone could bring their car and tool to Weedon on 25th May if the meet is on ? (I'm in Milton Keynes by the way).
I suspect the 15 over 13 reading shown in Mike C73's blog is about right, but I was then confused by his reference to making the scales coincide at 17, hence my desire to double check. I currently have mine set a bit tighter than that, so I'd like to do the check before running the engine too much more.
Also, I forgot to check the size of the auto-tensioner locknut when I had it apart, and now it's all covered with v-belts etc so I can't get a vernier on it.
I don't really want to strip all the v-belts off again and I think I would be able to get to it with a suitable ring spanner if I had one the right size - if someone could let me know the size it would be much appreciated.

Many Thanks,
Malcolm
Malcolm
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Re: Another timing belt question
I have a burroughs gauge (west oxfordshire) you can borrow any time. I hope to go to Castle coombe without the lotus of course. It's a bit further for you but is a nice day out.
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Re: Another timing belt question
Thanks for the offer Stu - Not sure whether I'll be at Castle Coombe.
I will be in touch
I will be in touch

Malcolm
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Re: Another timing belt question
I've done Weedon a couple of times recently, but next week end will definitely be Castle Combe for me.
Quite like to check my car with your Burroughs gauge Stu if you can bring it along.
Still to arrange, but I can drop by another time to MK and do a direct cross check with Malrigs.
Results could be interesting.
Tony
Quite like to check my car with your Burroughs gauge Stu if you can bring it along.
Still to arrange, but I can drop by another time to MK and do a direct cross check with Malrigs.
Results could be interesting.
Tony
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Re: Another timing belt question
I have one I’ll bring along too - would be good to compare as mine is the generic, rather than lotus specific one.MetBlue wrote: ↑Sat May 18, 2024 11:37I've done Weedon a couple of times recently, but next week end will definitely be Castle Combe for me.
Quite like to check my car with your Burroughs gauge Stu if you can bring it along.
Still to arrange, but I can drop by another time to MK and do a direct cross check with Malrigs.
Results could be interesting.
Tony
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Re: Another timing belt question
Thanks guys - hopefully this is a beautiful plan coming together, and the end result will be :
A bit of reassurance for me/us, and the option of a lower cost readily available cambelt gauge for all
Cheers,
Malcolm.
A bit of reassurance for me/us, and the option of a lower cost readily available cambelt gauge for all

Cheers,
Malcolm.
Malcolm
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Re: Another timing belt question
We're getting closer.a beautiful plan coming together
Learnt a lot about Burroughs gauge over the weekend and a "watch out" when using even some genuine article Burroughs gauges.
Some have a flat "shoe" others a round one. Complete guess on my part, but maybe older gauges have the flat shoe ?
The flat variety would work fine on the old Trapezoidal belts, see below photo ( Don't comment on the shape of the belt - it's a spare thats not under tension).

But use it on the later round tooth belt and the gauge will give a reading suggesting belt is tighter than it really is - The shoe can not sit on the root of the radius, note the shadow underneath.

Fortunately the shoe is not too hard and can easily be reprofiles to suit both the round toothed belts and trapezoidal.
Needless to say, Stu's gauge had the flat blade - but not any longer

Tony
What goes together.... Must come apart.