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1500 engine strip-down Question


molten

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Morning all

The original engine for my car has deck corrosion so will not be re-using. I picked up a spare engine last year (from a midget) and stripped down yesterday.
I noticed (with the sump removed and block upside down) that a number '3' was stamped on the lower edge of the crankcase adjacent to the middle main bearing. Yet.. the main bearing cap to the front of the engine also was stamped with '3', which makes me a little worried that in the past these two main caps may have been mixed up (or swapped round) for some reason!!! So they will be kept in this location on rebuild - just in case there is a reason for them being swapped round (hopefully not just an error on previous shelling), but may also get this checked out too.

The big-end bearings are marked '010' so pretty sure that crank has be re-ground previously. MB shell strangely are not stamped!
Cam followers were all 'dished' and cam lobes show signes of wear. As I plan to use mk3 grind cam on rebuild, this cam might be for the bin.
I am going to strip the original short block and check crankshaft and camshaft. The cam followers from this engine seem ok which leads me to think that the original cam may also be ok (will have to check though).

I cannot think of any obvious reason but, if the original cam and crank is within tolerances and turns out to not have been reground (long-shot), would it be fine to use these in the midget block (if i chose not to go down the mk3 grind cam route)?

Thanks
Scott

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No problem at all, but do number the followers so they match the lobes on the cam.
unstamped mains means they are still std size. handy, you may be able to get vandervell.
How about pistons, all std?? if the bores are OK, a hone and re-ring should do the trick. I did this on my last herald engine, built one from 2. And I weighed all the conrods and pistons, then got a set which were with 1g tolerance. (wifes digi cake scales) I think it helped, but you can never be sure. Certainly won't hurt.

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Hi Clive

Checked out original camshaft today and it does look much better than the one from the midget with the exception of very light and small rust discolouration in a couple of spots, so the cam could be used on rebuild.
Think new followers would be prefered on rebuild as only about 20 quid ish.
Is there such a thing as cam lobe dimensions published (with toleraces) that I could refer to to confirm if this original camshaft  is indeed usable?

Original engine block also had .010 shells too on crank, but the rear mains had a lot of surface corrosion between the shells rear journal and the chrome finish is gone (probably due to engine block stored in back of my van for months!!).
I also found that I have some variation between both my 2"-3" micrometers so can no longer trust either of them until they callibrated - damb >:(
I dont think there will be much difference between the 2 cranks so will look to have one reground (probably remove anther thou so that 020 shells can be ordered) and checked before new shells ordered.
Hope to measure bores tomorrow on the midget block, but i am expecting to have to have a rebore. Depending on bore size, do you know if any oversized rings could be all that is needed or would o/s pistons also be needed?

Cheers

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sorry my mistake, the crank main shells were also .010

Crank Journals (mains and big-end) still seem to be under sized by .010 (2.3014/5) but is it a good idea to just to refit new .010 shells or would another .010 grind be recommended.?

Camshaft journals all seem fine (1.965/6) and rear journal at 1.975 (-0.003 clearance at bore). Journals have 0.0397 run-out so again seems fine. The lobes 'look' to be in good condition and polish up nice with a slight rub with 2000 grit w&d.
I have DTI'd each lobe to measure theoretical lift but not sure this will tell me anything worthwhile
Is there any trusted DIY method to check the lobes on the camshaft for dimensional wear?

Will check cylinder bores on monday and see if rebore is needed.
Any pointers on checking bores?

Thanks
scott

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Apart from visual inspection looking for obvious marks/damage, about all you can do is compare the lift of all the lobes.  That is measure each one from peak to base circle with vernier calipers and compare.  If all the same, they are most likely ok.  The end ones normally die first in my experience.  If you have the followers than the condition of these can give useful clues as they tend to show damage first.  Don't re-use followers unless you can match them to their original lobe.  Some say original followers can be refaced and re-used.

Cheers

Nick

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Nick_Jones wrote:
Apart from visual inspection looking for obvious marks/damage, about all you can do is compare the lift of all the lobes.  That is measure each one from peak to base circle with vernier calipers and compare.  If all the same, they are most likely ok.  The end ones normally die first in my experience.  If you have the followers than the condition of these can give useful clues as they tend to show damage first.  Don't re-use followers unless you can match them to their original lobe.  Some say original followers can be refaced and re-used.

Cheers

Nick


Cheers Nick
I do see some varition between lobes but very minor. Any way to find out what the dim's on the standrd 1500 camshaft is/should be?

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If the crank surface is good then a re-shell will be fine. I believe it was originally recommended to change the big ends (and mains) every 40,000 miles or so.
I have reshelled several engines with no issues.
About to drain the oil on the toledo, the trackday got the oil rather too hot and the new bearings started knocking, but that was extreme (oil cooler to be fitted shortly, I really should have done that before  :B )

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Thanks clive.
Just seemed a little (in my head anyway) un-necessary to have crannk ground another thou when the journals are still showing thou undersize.
As there is the inevitable variation across journals (due to manual check with micrometer, readings still comeout at around 1 though under original spec or there abouts.

If regrind is not necessary then the £100 saved here could go to rebore or some other 'necessary' modification ;)

cheers
Scott

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