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#391 Steve220

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Posted 24 April 2024 - 09:05 PM

The cam journals look oil starved. What do the cam lobes look like for the pitted followers? What assembly lube was used?



#392 KTS

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Posted 24 April 2024 - 09:33 PM

Torco MPZ cam lube was used at assembly

Lobes are unsurprising a bit chewed up, with number 3 looking like it's gone through the case hardening on the nose

I've been in conversation with Keith Calver and his view is that there's enough issues with the cam itself (cam journals not finished, suspicion from wear pattern there's insufficient taper on the lobes) for that to be the cause of the follower damage and the bearing material in the oil.

Next step is to choose a replacement cam and go again..

#393 KTS

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Posted 30 May 2024 - 07:32 PM

back on it again now that the block and crank have come back from the machine shop with new cam bearings and a regrind

 

the block was looking decidedly shabby when it came back, so that needed stripping back and repainting; this time a closer match to the body colour

 

1EJComy.jpg

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hopefully should get a bit more time on it at the weekend to clean up a few more parts before I start putting it back together again



#394 KTS

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Posted 07 June 2024 - 08:42 PM

i did get a bit more done last weekend, but it didn't end well..

 

cleaned and refitted the crankshaft and checked the main bearing clearances with 2 out three showing less than 1.5thou, but the third one was showing 2thou, so I lapped the base of the cap to see if it would help.

 

it didn't.  what it did was lock the crank solid when i did the bolts up.  after much wailing and gnashing of teeth, with visions of having to get the block line bored to rectify my stupidity i reasoned that if i'd taken too much material away, as long as i'd done it evenly i might be able to shim the cap to get it back to usable.

 

after many hours and sacrificing several sets of feeler gauges i managed to get to a point where i could bolt down the cap with 4thou packing and get a reasonable bearing clearance, so ordered some 4thou shim stock and made up a set of shims.

 

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it's not perfect, but it'll have to do.

 

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3 thou crankshaft end float 

 

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stripped, inspected, cleaned and measured the oil pump - tolereances are all good, but i did have to clean up the underside of the rotor as it was scoring the base of the pump

 

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refitted the timing gear back plate, camshaft and pulleys, checked cam end float and pulley alignment

 

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put the chain on ready to start timing the cam in this evening, and then realised I hadn't fitted the oil gallery plugs so spent the evening taking the timing gear and back plate off and fitting the plugs instead.

 

getting there....



#395 evoderby

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Posted 08 June 2024 - 05:11 PM

STOP!



#396 evoderby

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Posted 08 June 2024 - 05:19 PM

Your car is way too nice to bodge the bearing cap clearance like that. I understand that you look forward to get things running rather than spend more time sorting problems….but this really isn’t the way forward.

 

Why does the crank lock up, what has changed since you last built up the short block? You mention a regrind….of the crank? How does it measure up? Do your bearings measure up ok? Something must be amiss. 



#397 KTS

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Posted 08 June 2024 - 07:20 PM

Your car is way too nice to bodge the bearing cap clearance like that. I understand that you look forward to get things running rather than spend more time sorting problems….but this really isn’t the way forward.

 

Why does the crank lock up, what has changed since you last built up the short block? You mention a regrind….of the crank? How does it measure up? Do your bearings measure up ok? Something must be amiss. 

 

the crank locks up because i'm an idiot and took way too much off the bearing cap when trying to adjust the bearing clearance.

 

the block doesn't have enough life left in it to warrant getting it line bored, so rather than just scrapping it and starting again i figured i might as well take the opportunity to see if i could bush fix it.



#398 KTS

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Posted 08 June 2024 - 08:28 PM

having fitted the oil gallery plugs it was time to do the cam timing - vernier timing gear certainly makes adjusting it a simple exercise. 

 

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a quick look at the big end bearing clearances..

 

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...check the idler gear end float; 4thou will do

 

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...sluice out the gearbox with paraffin

 

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..and re-attach it to the block

 

01nqwU0.jpg



#399 KTS

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Posted 10 June 2024 - 08:44 PM

next job on the list was to pack all the drillings for the gear box fasteners in the block with grease to keep water and crap out

 

8MWIYeV.jpg

 

..give the gearbox and transfer case a good scrub, give it a coat of ACF50, refit the oil filter housing and transfer pipe, and fit the flywheel and crank pulley

 

kn33WNb.jpg

 

ready to put back in the car.  cylinder head will get refitted once the engine is in and i've spun it over to get some oil through the system



#400 KTS

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Posted 13 June 2024 - 08:41 PM

putting the engine back in turned out to be a bit of a faff as i couldn't get the pot joints back onto the output shafts, so decided to knock the pots of the driveshafts, fit them to the box and then drop the motor back in.

 

not having three hands, i needed to come up with a way of holding the driveshaft in place so i could knock the pot joint off with a long screwdriver, so came up with this, which works a treat

 

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..which meant i could finally get the motor back in

 

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