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I guess I'll do a rebuild too....


Luka-P

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Good luck with this project. Doing it yourself is the best way to learn. All my (limited) mechanical knowledge I got from messing about with engines at your age. Although it was mini's and ford escorts in my time, much easier.

 

Thanks, as said before, I dont think Im lacking help if I get stuck. Lots of people are willing to pitch in and lend a hand!

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I have the engine completely stripped. The final part bought a bit of bad news. I first found the culprit big end shells. As you can see from the pictures, the fourth big end from the front had excessive damage on the shell and, possibly, the crank journal. The shells were quite swollen on both the rod and end cap side. I have also noticed scoring on the cylinder walls, mostly in the fourth cylinder from the front but also on the third. The others don't look too bad. A re-bore looks like its on the cards. :(

 

I have taken some pictures for your opinions/advice but a proper look by the machine shop will be needed for a decision. I think I know what the answer will be though.

 

There was no ridge on the tops of the cylinders however. Quite a surprise.

 

The pictures are as follows, from first to last.

 

Rear two cylinders from right.

Middle two cylinders from right.

Front two cylinders from right.

Rear two cylinders from left.

Middle two cylinders from left.

Front two cylinders from left.

Fourth and third journals on the crankshaft.

Damaged shells.

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The block, crankshaft, rods and pistons went to the machine shop this morning. He was quite impressed saying it had big end problems. He said the journals didn't look too bad and the bores were not scored as much as he thought they would be either. Everything is going to have a full check over in comparisson to the tolerances. I'll bring some more information when it comes!

 

 

Cheers.

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Hello People,

 

Nice update for you all.

 

Ive had the block, crank, rods and pistons at the machine shop for a few days. Through word of mouth I heard the person I first took it too wasn't very good. I decided I didn't want him to work on the engine so I called him and said I will collect everything later that day. He proved his incompitence to me today when I arrived, by telling me the crank just needed a quick polish and the bores needed a quick hone. I didnt think this was quite right and I felt a bit akward with his decision due to it only coming from a quick look ie no measuring/testing etc. I said I thought I should get a second opinion. I then took it to a different person, a veteran, knows the works etc. He measured it up whilst I was there and the journal on the crank where the big end went on was 8 thou out! Shows how much the first guy knew! So a better crankshaft is needed. (Luckily Keron has a nice TT bottom end waiting for collection next week :D) He did say we could grind it and go with bigger bearings but I said I wasnt comfortable with that. He did however say the bores were ok, they just need honing. There was no lip at the top and the scratches were minute.

 

Everything is going to be worked on in the next couple of days. All parts will be acid dipped or part washed. All I need to do is to get the shopping list together!

 

Cant wait to be working with new, shiney, clean parts!

 

Luke.

Edited by Luka-P (see edit history)
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  • 3 weeks later...

Nice Update:

 

I got the block, crankshaft, pistons and rods back from the machine shop the other day. Since then I have been prepping my work area and just generally organising myself for the rebuild stage of this little project. Things have been going nicely, the garage is clean and tidy, my tools are organised and Im ready to go!

 

Right, the machining work. The block was acid dipped prior to any machining. It was then honed and checked for flatness. It was then dipped again and thoroughly cleaned. The pistons and rods were cleaned and all checked to tolerance. They grooves were then cleaned and the whole assembly washed once again. The crankshaft was measured after cleaning and then polished and protected.

 

When I got the block back home I gave it a really good clean using solvents, a brush and an air line to remove debris. I then applied a few coats of engine lacquer, red, the best colour IMO. Four coats to be exact, one applied and then left to dry until the next night. Its turned out great if you ask me.

 

All the mating surfaces, such as the top of the block, all gasket faces etc, were then scraped and cleaned. The whole block was then aired down to ensure there was no debris.

 

I then swept the garage out a few more times whilst the block was protected. All the parts are now layed out ready to be assembled and I can begin to get this beauty back together.

 

Ta.

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Cheers Ed, keeping things in place makes good practice, saves wasting time looking for tools etc. Makes life a doddle.

 

Quick question for everyone especially all our good tech folk! I have two sets of main caps, the original ones which came on my block and another set from the block I bought, these are in far better condition. Question is; which should I use? The ones from the donor block are in far better condition and have some colour in them, the original ones are just black but the bearing faces are ok. Which would be best to go for? Im using ACL bearings so as long as the oil clearance is ok would it really make a difference?

 

Any help would be great.

 

Luke

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  • 5 weeks later...

Ok a nice update for you all.

 

Apologies for the lack of photographs. I tend to get stuck in and don’t really have the time to keep taking photos. I have however taken some progress shots.

 

Yesterday and today I did the work on the bottom end. It's nearly complete just a few odd things to clean and put on. Previously I had installed the pistons along with new rings into the newly honed bores. Each compression ring was placed into the bore and the gap was measured using a feeler gauge. After some tinkering they were all within tolerance. Fresh engine oil was applied to each piston after the rings had been put on. The rings were then compressed and pushed into the bores.

 

So yesterday I began by putting the new main bearings, courtesy of Paul, into the block along with the thrust washers. I then applied some assembly red to them all and placed the crank shaft into the block. The shells were then located into the main caps. I placed a strip of Plastigauge onto the main journals of the crankshaft and then put the main caps into their positions. They were then tightened to torque in the sequence shown in the manual. The caps were then removed and, using the scale that comes with Plastigauge, the oil clearance was measured on each journal. They were all within tolerance. The same process was repeated with the big end bearings and they were also excellent. A great find with that crankshaft! Assembly red was then placed onto all sliding surfaces and onto bolt threads and under the heads. Everything was then bolted down to torque.

I was now ready to install the rear crank seal. I put Hylomar blue on the housing and tapped the seal until it was flush. So MP grease on the inner edge and then installed onto the block. The front seal was installed in the same way into the oil pump and the oil pump was installed.

 

I then went on to do the second sump. Silicone RTV was applied to the sump grooves and then placed onto the block. The bolts were then torqued down. The baffle plate, pick-up pipe and level sensor were then installed. Finally I put the bottom sump onto the engine.

 

Other bits and pieces were installed including the oil filter bracket and oil cooler, coolant pipes, drive plate, Cambelt drive and crank pulley bolt. The engine is starting to take shape now and may be back sooner than I expected. The head has gone to the machine shop to be skimmed and tidied up.

 

Luke.

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Coming along nicely there! By the way, when you check oil clearance with plastigauge you are supposed to assemble it dry (i.e. no oil or assembly lube) - otherwise the lube can affect the reading.

 

I had thought that myself Simon. I originally checked the clearance dry and then contemplated on whether the crank would, theoretically, be sat low and therefore not concentric to the bearings. Not much in it to be honest but all checked out ok.

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