'Budget' DIY Engine Rebuild
#181
Scooby Regular
Thread Starter
DIY v3/4 Head Port & Polish
OK well after looking at all the examples of how a port/polish job SHOULD be done, I picked up a Dremel for £4 from a boot sale and with a few small grinding stones, sanding rolls, abrasive buffs and brass brushes, I've got a much better finish, which tbh is as far as I want to go with it. Altogether, I've 'blunt-knife-edged' the inlet port divider and tidied the ports themselves up to a decent finish, polished the combustion chambers and taken any sharp edges out (mainly between the inlet/exhaust seats) and ported the exhaust ports. The inlet ports were fairly straightforward with a Dremel, but the exhaust ports were much harder because they are smaller and more twisty. But I did manage to grind out the casting blobs that were all over the bowl area around the exhaust valve guides. Next step will be to do the same to the other head then start assembling. TOP TIP: If you're DIY porting/polishing your own heads, forget using an electric drill. You need a mains electric (or air) die grinder/Dremel/rotary tool. This will be small and fast enough to do the job properly.
Overview of both chambers:
Polished combustion chamber looking down into the bowls under the valve seats:
Mildly knife-edged inlet ports, casting defects like steps, seams and bobbles eradicated. You can see where the inlet valve seats join into the port, it looks rough but it is smooth to the touch now, and I didn't want to take any more material out to blend it perfectly because that would alter the shape of the ports too much and from what I understand the valve throat needs to stay narrow:
Overview of both chambers:
Polished combustion chamber looking down into the bowls under the valve seats:
Mildly knife-edged inlet ports, casting defects like steps, seams and bobbles eradicated. You can see where the inlet valve seats join into the port, it looks rough but it is smooth to the touch now, and I didn't want to take any more material out to blend it perfectly because that would alter the shape of the ports too much and from what I understand the valve throat needs to stay narrow:
Last edited by silent running; 14 July 2008 at 11:46 PM.
#183
Scooby Regular
Thread Starter
Block is off for boring right now. Just waiting for it to come back. The 'balance of account' is pretty complex at the moment as I've been selling off unneeded bits as well as buying. Once the build's done and working I'll do the final reckoning but at the moment, pistons and rods have cost only £500 from CDF. I've kind of avoided putting prices up on here up to now, but a lot of people have been asking so there it is. You can't import them directly yourself from the States for much less than that, and then you have to take a chance on import duty, VAT etc.
#184
Great work / read mate. Doing a similair thing myself at the moment.
What you going to use for clearances when it comes to installing big end / main bearings; plastigauge or dial bore gauge / micrometer?
Also, what's your current status ?
What you going to use for clearances when it comes to installing big end / main bearings; plastigauge or dial bore gauge / micrometer?
Also, what's your current status ?
Last edited by nullfork; 19 July 2008 at 01:35 AM. Reason: typo
#185
Scooby Regular
Thread Starter
I'm just using a digital vernier calipers to measure everything up. As long as all the dimensions are right, I'm just going to put it together and basically cross my fingers! The block has just come back from boring today, so I now have a pair of ported and polished v4 heads ready for STi3/4 valvetrain, and a block with bearings, crank, rods and pistons ready to be assembled. ARP head studs and hard anodised front pulleys are on the way from CDF. I'll be getting a new modine oil cooler and some Millers running in oil from AS Performance next month.
So now I am at the moment I have been both looking forward to and dreading at the same time, having never assembled an engine before...there's no way I can do any other little jobs, I have to get right on and start building everything up. Any tips from anyone about how to proceed with building up the short block? Or the heads? I have assembly lube, engine oil and Threebond 1215 at the ready. Where they all go though...?
So now I am at the moment I have been both looking forward to and dreading at the same time, having never assembled an engine before...there's no way I can do any other little jobs, I have to get right on and start building everything up. Any tips from anyone about how to proceed with building up the short block? Or the heads? I have assembly lube, engine oil and Threebond 1215 at the ready. Where they all go though...?
#186
Scooby Senior
Join Date: Feb 2003
Location: West Midlands
Posts: 1,903
Likes: 0
Received 0 Likes
on
0 Posts
I used the procedure below for assembling the heads to the short block using standard (re-used) head bolts.
Tightening sequence of bolts:-
.................exhaust side...................
.....................3 1 6..........................
front of engine......... Rear of engine ....
.....................5 2 4..........................
..................inlet side........................
Then tighten torque and angle in the following stages, in the sequence above
1. 29 N/M OR 22 FT/LB
2. 69 N/M OR 51 FT/LB
3. BACK OFF 180 DEG. (REVERSE SEQ 6-1)
4. BACK OFF FURTHER 180 DEG (REVERSE SQ. 6-1
5. RE TORQUE 29 N/M OR 22 FT/LB (1-6)
6. 80 TO 90 DEG. (NOT OVER 90)
7. 40 TO 45 DEG. (NOT OVER 45)
8. NO.1 AND NO.2 40 TO 50 DEG. FURTHER (NOT OVER 50)
Step 1-2 are basically for settling the gasket, as step 3-4 pretty much take all the torque off. Put a little bit of oil (or better still a small blob of moly grease) on each bolt thread.
Don’t guess the angles. Get an angle disc for your torque wrench.
I managed to buy a cheap angle gauge from a local motor factor shop for 4.99, the same gauge was going for about 10 gbp on ebay. I will try to post a link of the same gauge.
I would check the crankshaft/bearing clearances using plastigauge. At least you will have peace of mind that the clearances are to spec as you have re-used the original crank.
Ticky
Tightening sequence of bolts:-
.................exhaust side...................
.....................3 1 6..........................
front of engine......... Rear of engine ....
.....................5 2 4..........................
..................inlet side........................
Then tighten torque and angle in the following stages, in the sequence above
1. 29 N/M OR 22 FT/LB
2. 69 N/M OR 51 FT/LB
3. BACK OFF 180 DEG. (REVERSE SEQ 6-1)
4. BACK OFF FURTHER 180 DEG (REVERSE SQ. 6-1
5. RE TORQUE 29 N/M OR 22 FT/LB (1-6)
6. 80 TO 90 DEG. (NOT OVER 90)
7. 40 TO 45 DEG. (NOT OVER 45)
8. NO.1 AND NO.2 40 TO 50 DEG. FURTHER (NOT OVER 50)
Step 1-2 are basically for settling the gasket, as step 3-4 pretty much take all the torque off. Put a little bit of oil (or better still a small blob of moly grease) on each bolt thread.
Don’t guess the angles. Get an angle disc for your torque wrench.
I managed to buy a cheap angle gauge from a local motor factor shop for 4.99, the same gauge was going for about 10 gbp on ebay. I will try to post a link of the same gauge.
I would check the crankshaft/bearing clearances using plastigauge. At least you will have peace of mind that the clearances are to spec as you have re-used the original crank.
Ticky
#187
Scooby Senior
Join Date: Feb 2003
Location: West Midlands
Posts: 1,903
Likes: 0
Received 0 Likes
on
0 Posts
#188
Scooby Regular
Thread Starter
Cheers for that. I have an angle gauge already, but where do you get plastigauge from and how does it work? From what I've seen you lay it in the clearance you want to measure, tighten everything down and work out the gap from the scuffing?
#189
Scooby Senior
Join Date: Feb 2003
Location: West Midlands
Posts: 1,903
Likes: 0
Received 0 Likes
on
0 Posts
You can get it from ebay or Plastigauge (M630) - Frost Auto Restoration Techniques
I would just double check the measurement range before buying.
Ticky
#191
Scooby Regular
Thread Starter
So let me just check that I've got this right... I'll actually trial fit the main and big end bearings and basically assemble the crank and rods but with plastigauge stuff in the clearance spaces?
I can see how you'd measure the big end clearances, presumably just tighten the caps down then open them up again to look at the plastigauge stuff. But how would I do the mains? Actually bolt the two block halves together with the bearings and crank in place?
Two other questions for the engine builders on here:
1. Do I use assembly lube everywhere the manual normally would recommend you use engine oil to assemble? And one side of the bearings is put in dry?
2. The manual shows to assemble the crank/rods and fit them inside the block halves then bolt the crankcase together, then attach the four pistons afterwards. Is there any reason why I couldn't attach two pistons to their rods first of all, then fit them into the bores with the big ends dangling through the bottom, then attach the crank, then put the block halves together, so I'd only have to mess about with piston pin access holes on one half of the block?
I can see how you'd measure the big end clearances, presumably just tighten the caps down then open them up again to look at the plastigauge stuff. But how would I do the mains? Actually bolt the two block halves together with the bearings and crank in place?
Two other questions for the engine builders on here:
1. Do I use assembly lube everywhere the manual normally would recommend you use engine oil to assemble? And one side of the bearings is put in dry?
2. The manual shows to assemble the crank/rods and fit them inside the block halves then bolt the crankcase together, then attach the four pistons afterwards. Is there any reason why I couldn't attach two pistons to their rods first of all, then fit them into the bores with the big ends dangling through the bottom, then attach the crank, then put the block halves together, so I'd only have to mess about with piston pin access holes on one half of the block?
#192
Scooby Regular
Thread Starter
Maybe, but I've still got to lap in a set of valves, assemble the heads, and get the valve clearances all proper with the shims I've got.
#193
Assemble one half, coat the crank bearing surfaces and lower it into place and then offer the other block half up making sure that all the block mating surfaces are dry and oil/lube free. Also use the assembly lube when fitting the cams.
2. The manual shows to assemble the crank/rods and fit them inside the block halves then bolt the crankcase together, then attach the four pistons afterwards. Is there any reason why I couldn't attach two pistons to their rods first of all, then fit them into the bores with the big ends dangling through the bottom, then attach the crank, then put the block halves together, so I'd only have to mess about with piston pin access holes on one half of the block?
#194
Scooby Senior
iTrader: (12)
Join Date: Apr 2006
Location: south wales rhondda
Posts: 4,067
Likes: 0
Received 0 Likes
on
0 Posts
thought you might be intrested in this link fella hope it helps with your build its a 2.5 build but im sure its the same for 2 liter and have you had any progress on the build?? here is the link Subie TV
#195
Scooby Regular
Thread Starter
Yes I've made some more progress, slowly! I've now managed to get the plugs out for the oil and water galleries in the heads and cleaned them out thoroughly, first with carb cleaner, then a hosepipe then WD40 into the oilways and the rocker side of the heads to keep them from going that funny colour that aluminium does if you leave it wet.
I've now got one of the block halves on the bench to drill out a crankcase bolt that had sheared off inside. It's slow going but I think I'll get it out in the end. Luckily it was one of the 'backbone' bolts so easy to get at.
Once that's out, I'll be degreasing the block halves just to make sure there's no honing oil with swarf in it lying around, and basically blasting the thing clean. Then I'll re-oil the bores to keep them rust-free and start trial fitting the crank and main bearing shells into the block with plastigauge to check the clearance. Then the crank will come out and the rods and big end shells will go on, again with plastigauge to check the big end clearance. If all checks out, then I will start assembling the block halves together with all new seals.
Simultaneously I am tinkering with putting the STi valvetrain into the heads.
I've now got one of the block halves on the bench to drill out a crankcase bolt that had sheared off inside. It's slow going but I think I'll get it out in the end. Luckily it was one of the 'backbone' bolts so easy to get at.
Once that's out, I'll be degreasing the block halves just to make sure there's no honing oil with swarf in it lying around, and basically blasting the thing clean. Then I'll re-oil the bores to keep them rust-free and start trial fitting the crank and main bearing shells into the block with plastigauge to check the clearance. Then the crank will come out and the rods and big end shells will go on, again with plastigauge to check the big end clearance. If all checks out, then I will start assembling the block halves together with all new seals.
Simultaneously I am tinkering with putting the STi valvetrain into the heads.
#198
Scooby Regular
Thread Starter
Bolt problem is solved. In the end I couldn't get the old bolt thread to drop out like I've been able to in the past, it seemed almost welded into the block. Anyway, I just overbored the whole thing to make a plain hole through and after making a little extra clearance on the outside for the bolt head and reshaping a longer bolt's head with the trusty 'Dremel' so it would fit snug, it seems to work. When it comes to the final assembly, I'll just do up all the other crankcase bolts to the right torque and then tighten my nut and bolt combo last. It should hold, what with all the other pretty serious bolts there holding the crankcase halves together. Only problem was that the bolt remains were easy to pick up with a magnet, but of course where I slightly drilled into the block as well, the aluminium swarf got everywhere. I think I've got it all though.
Today I'm going to be checking the clearances on the mains and big ends. I'll post pics tonight if I get the chance.
Today I'm going to be checking the clearances on the mains and big ends. I'll post pics tonight if I get the chance.
#202
Scooby Regular
iTrader: (22)
500 miles on the nastiest cheapest oil you can find. No more boost than 0.5bar and no more than 4000rpm. Don't just cruise everywhere at 4000rpm though vary the revs and do some engine braking.
After 500 miles drop the oil, change the filter, refil again with nasty cheap oil.
By nasty cheap oil I mean non synthetic mineral stuff. Halfords 10w 40.
This allows a bit of wear whic is exactly what you want to bed everything in.
1 bar and a maximium of 5500rpm again varied. Do this for another 500 miles.
after 500 miles (1000 total so far) drop the oil, replace the filter and then fill it with mobil one 15w 50 fully synth. get your full map done and away you go. Then drop your oil every 7500 miles
After 500 miles drop the oil, change the filter, refil again with nasty cheap oil.
By nasty cheap oil I mean non synthetic mineral stuff. Halfords 10w 40.
This allows a bit of wear whic is exactly what you want to bed everything in.
1 bar and a maximium of 5500rpm again varied. Do this for another 500 miles.
after 500 miles (1000 total so far) drop the oil, replace the filter and then fill it with mobil one 15w 50 fully synth. get your full map done and away you go. Then drop your oil every 7500 miles
#203
Scooby Regular
Join Date: Mar 2008
Location: Torbay, Devon
Posts: 566
Likes: 0
Received 0 Likes
on
0 Posts
500 miles on the nastiest cheapest oil you can find. No more boost than 0.5bar and no more than 4000rpm. Don't just cruise everywhere at 4000rpm though vary the revs and do some engine braking.
After 500 miles drop the oil, change the filter, refil again with nasty cheap oil.
By nasty cheap oil I mean non synthetic mineral stuff. Halfords 10w 40.
This allows a bit of wear whic is exactly what you want to bed everything in.
1 bar and a maximium of 5500rpm again varied. Do this for another 500 miles.
after 500 miles (1000 total so far) drop the oil, replace the filter and then fill it with mobil one 15w 50 fully synth. get your full map done and away you go. Then drop your oil every 7500 miles
After 500 miles drop the oil, change the filter, refil again with nasty cheap oil.
By nasty cheap oil I mean non synthetic mineral stuff. Halfords 10w 40.
This allows a bit of wear whic is exactly what you want to bed everything in.
1 bar and a maximium of 5500rpm again varied. Do this for another 500 miles.
after 500 miles (1000 total so far) drop the oil, replace the filter and then fill it with mobil one 15w 50 fully synth. get your full map done and away you go. Then drop your oil every 7500 miles
#204
Scooby Regular
Thread Starter
Well what I heard is 15 minutes running at up to 3000 revs on ****ty oil then drop it then another 100 miles on the same stuff then change, gradually working up in boost and revs and make sure it gets plenty of high loads i.e. low revs/high gears, change again at 500 miles for the proper synthetic
#206
Scooby Regular
Thread Starter
Nice one Chris. I've just finished measuring the main bearing clearances with plastigauge - what a pain in the ****, but still at least now I know...0.030mm on most with one at 0.035. It's all within limit though so it'll do. Tomorrow I'll do the big ends, and assuming they work out OK, I'll start assembling the block. Pictures coming soon.
#210
Scooby Regular
Thread Starter
Funny you should say that, I'm just about to upload some snaps, and about to pop out to the garage to check the big end clearances with plastigauge. Here goes...
Block halves back from being overbored and honed to 92.5mm for my new pistons. I've also drilled out the sheared off crankcase backbone bolt and replaced it with a plain hole through which I'll use a long bolt and nut instead.
ACL Race Series bearings going into position for a trial fitting of the crank/main bearings/block so I can check the clearance on the mains with Plastigauge. Target clearance is up 0.035mm max once everything's tightened down. The bearings only can fit one way and I just knocked them lightly into place with a rubber mallet. The one that looks like it has copper flanges down the side is the centre thrust bearing on #3 main, presumably this keeps the crank from moving back and forth in the block. All the early lumps use these centre thrust cranks, the later ones use rear thrust with a thrust bearing in the #5 position.
Trial fitment of crankshaft onto main bearings. What you can't see is a little strip of Plastigauge that I've laid over each of the five bearing shells so that once it's all tightened up they should spread out and show me what oil clearance is in there. Too much clearance = low oil pressure. You may recall I got this crank out of the first CDB I acquired.
Here you can see into assembly without the pistons; I've not screwed the oil spray jets back in and you can see the hole where one goes at the bottom of the right hand cylinder.
Overview of the whole crankcase block put together - yes you really have to do this and torque up all of the dozen or so crankcase bolts correctly to get the clearance measured with Plastigauge, then take it all apart again!
The results of that trial build - a red smear on each main bearing surface on the crank showing how much clearance there will be once everything's tightened down properly. The width of this smear is measured up against a little ready reckoner card that you get with the Plastigauge and it shows that this is 0.030mm. Close to the outer limit, but within spec and it's pretty even across all five bearing surfaces, so I'll go with it.
Block halves back from being overbored and honed to 92.5mm for my new pistons. I've also drilled out the sheared off crankcase backbone bolt and replaced it with a plain hole through which I'll use a long bolt and nut instead.
ACL Race Series bearings going into position for a trial fitting of the crank/main bearings/block so I can check the clearance on the mains with Plastigauge. Target clearance is up 0.035mm max once everything's tightened down. The bearings only can fit one way and I just knocked them lightly into place with a rubber mallet. The one that looks like it has copper flanges down the side is the centre thrust bearing on #3 main, presumably this keeps the crank from moving back and forth in the block. All the early lumps use these centre thrust cranks, the later ones use rear thrust with a thrust bearing in the #5 position.
Trial fitment of crankshaft onto main bearings. What you can't see is a little strip of Plastigauge that I've laid over each of the five bearing shells so that once it's all tightened up they should spread out and show me what oil clearance is in there. Too much clearance = low oil pressure. You may recall I got this crank out of the first CDB I acquired.
Here you can see into assembly without the pistons; I've not screwed the oil spray jets back in and you can see the hole where one goes at the bottom of the right hand cylinder.
Overview of the whole crankcase block put together - yes you really have to do this and torque up all of the dozen or so crankcase bolts correctly to get the clearance measured with Plastigauge, then take it all apart again!
The results of that trial build - a red smear on each main bearing surface on the crank showing how much clearance there will be once everything's tightened down properly. The width of this smear is measured up against a little ready reckoner card that you get with the Plastigauge and it shows that this is 0.030mm. Close to the outer limit, but within spec and it's pretty even across all five bearing surfaces, so I'll go with it.