knocking on start up

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philthehill
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Re: knocking on start up

Post by philthehill »

That's good.

kevin s
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Re: knocking on start up

Post by kevin s »

The bible arrived yesterday.
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Seems to agree pretty much with the plans we had, some very usefull tips on how to modify the head, when he evetually gets a hif carb and LCB manifold we hope to be getting around 60hp.
Mind you having a head gasket that isn't leaking and 4 matching pistons/compression ratios would probably be a big improvement on it's own.

While we are waiting we are going to trial fit the mx5 box on the spare engine so I can check clearances and make a pattern for the rear engine mount which hopefully will pretty much be a case of moving the gearbox x member back about 10 inches and making a bracket for the gearbox.

We also have managed to damage the radiator, anyone any experience on the alloy ones widely available ?
kevin s
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Re: knocking on start up

Post by kevin s »

We got the spare minor engine out and put it on the stand.
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This is the first engine I bought which had got water in the crankcase rusting most of it. We pulled it to pieces, one piston took some persuading and most of the cam followers and little ends are tight but otherwise it was suprisingly servicable
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We are thinking of using this crank, although it measured up ok the original one has a slight ridge on the centre main.

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You can just feel it but it's probably only a thou or 2.

The one out of the rusty engine has no apparant wear at all there is some marking to the journals but it's only on the surface. Otherwise there is a bit of surface rust on the webs etc but nothing major.

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oliver90owner
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Re: knocking on start up

Post by oliver90owner »

You can just feel it but it's probably only a thou or 2.

What is it? Is that the raised edge or the diameter?

I thought you said you had measured the crank and found it within spec. If two thou on one side, that could mean 4 thou on the diameter. Probably (or possibly) more? What are the service limits for the crank mains?
les
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Re: knocking on start up

Post by les »

Sounds like you might have got lucky with your ‘spare’ crankshaft. Hope it cleans up ok.

kevin s
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Re: knocking on start up

Post by kevin s »

The slight ridge is only on one side of the crank on the centre main, I would expect this to be related to the firing loads of cyl 2 and 3 being in the same direction. It measured as around a thou down from the nominal but I'm not sure how accurate that is given the foot of the micrometer is virtually the same diameter as the groove. The plan is to check both of them with Plasti guage at 2 perpendicular directions, I think this is about the most accurate way of checking bearing clearances. Both engines are factory spec and have not been re-bored or had the cranks ground.

Andrew cleaned all the rust off the webs etc yesterday with a wire brush, just need to wait for some emery paper to arrive so we can go over the journals .
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Virtually all the parts have now arrived, just need to get one of Andrew's mates to drop off the pistons at the machine shop (we are quarantining because my wife has an operation next week)
philthehill
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Re: knocking on start up

Post by philthehill »

If you want to ruin the journals use emery cloth!!!!
If you need to clean up the journals use very very fine (at least 2000 grade grit) oiled (3 in 1 is good) wet and dry paper.
Use the wet and dry radially around the journal - do not go across the journal.

Propshaft
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Re: knocking on start up

Post by Propshaft »

Years ago when polishing journals we use to use a strip of dead emery cloth i.e. Really worn out , turn it over and use the cloth face to polish
kevin s
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Re: knocking on start up

Post by kevin s »

I have used fairly fine (around 300 grit) emery before without any problems after being advised to do this 30 odd years ago by an experienced engine builder. But after some research as you say that is not the current thinking, the general consensus seems to be to start with some oiled 600 grit wet and dry spun with a flat strap wrapped twice around the journal then as you say work up to 2000 grit used the same way, as we have all of this I will be having a go this afternoon then we will give it a test in the spare block with some plasti gauge.

Given the lengths we are going to if there is any doubt we will just splash out £140 on a re-ground crank.

Also ordered some brushes and 10L of cleaner so we can be really sure the oil drillings are cleaned out properly.
kevin s
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Re: knocking on start up

Post by kevin s »

Tried the 2 cranks in the spare block today with plastigauge, with the shells which came out of our engine which still have white metal on them the original crank came out at 4 thou and the second one came in at 2.5 thou, I reckon with new shells that will be fine.

Then I cleaned up the second block and covers today, and ran a hone up and down the bores. We will assemble all the useable parts back into this so it could easily be made into a running engine if required.
kevin s
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Re: knocking on start up

Post by kevin s »

Still waiting for the machined parts back (only dropped the pistons off a week ago) but in the mean time we have built all the best left over parts into what was the rusty engine, the block cleaned up well and the standard size bores honed up to leave a pretty clean finish with just a shallow wear ridge at the top left (probably would hone out if I spent a bit more time on it). Out of the 2 engines we had a matching set of 4 good standard size pistons, our engine had a perfect cam and followers plus the worst of the 2 but a still serviceable cranks. So with new rings, a new gasket set and a new timing chain this would also make a servicable engine, for now we will seal it up coat it internally in chain oil and put it in storage. Before this though I will fit all the MX5 gearbox conversion parts we have made so far to it and test fit this in the car to give us accurate dimensions for the gearbox crossmember (hoping I can pretty much just move the standard one rearwards by about 10 inches) and the propshaft.
jagnut66
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Re: knocking on start up

Post by jagnut66 »

You can always fit a 5/8" ball bearing which is a well known and well used modification. The ball bearing will seal and most importantly not jam.
http://www.minispares.com/product/Class ... o%20search

An excellent remedy Phil and fairly simple to fit, providing the original isn't jammed in there when I go to take it out. :roll:
I've ordered two, prevention being better than cure and considering how much of a bargain price they are (the postage actually is more than the cost of the parts!), one for Sally's engine and one for the next Morris Minor........
Best wishes,
Mike.
1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
kevin s
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Re: knocking on start up

Post by kevin s »

Yes we have got one to go in this as well, the old one is free though.
jagnut66
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Re: knocking on start up

Post by jagnut66 »

Hi,
I got round to changing the relief valve in Sally's engine today. It went well, as the valve itself wasn't stuck in position but I did wonder when it wasn't on the end of the spring when this was withdrawn. However I had my trusty flexible magnet to hand, which inserted neatly into the hole in the block and I soon had the valve out.
https://www.ebay.co.uk/itm/202100794801 ... SwU8hY5Q4K
It's clean and undamaged, so it and the original spring will go my 'free spares' pile, ready for the 2022 National.
The replacement Mini item went in a treat.
Once I get my refurbished 1098 head back from Mansfield Engines (8 unleaded valve seats, skim and mild port), I shall sort out Elsie May and replace her relief valve at the same time, I just hope it comes out as easy........
Best wishes,
Mike.
1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
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