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Crankshaft is beautiful!. Now the rods need some love :)

Shot peening is a common thing to do to extend their life, and what I will be doing
Pete
 

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Hi there, in your pictures of 6 pistons, on the top of the dome of pistons 4, 5, 6 is there a number that's something along the lines of 7222? If so they are Borgo 10.4's. Those three look like it anyway, from that picture anyway.

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@stevespiderguy , If this has already been mentioned, I apologize. Measuring the liners at the indicated spots, measuring for taper and out of round can be brain numbing. Looking for the maximum taper and out of round of .0004" makes me cross-eyed. If I am considering reusing the P&L's, I just measure the piston to liner clearance with long feeler gauges. You can buy a set ( 11'' long, .0015" to .040" ) on Amazon for less than $20. The (Alfa) Factory Engine Overhaul Manual gives a piston to liner clearance of .0016" - .0023". I have rebuilt street engines with as much as .004" with no issues. Be sure to check the fit of the pin and pin bore in the pistons, too. As for the rods, I always replace the small end bushings (give the machine shop the piston pins and they will size - hone the bushing to fit properly). My machine shop guy also (as a matter of course) takes a thousand or two off the big end cap and then rebores the big end to spec. He says that they all get "ovalated" and this makes the big end round (and to spec) again. If the Forum has Publication PA8777 ENGINE OVERHAUL MANUAL, read it. It's a wealth of information.
 

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Discussion Starter #64
Crankshaft is beautiful!. Now the rods need some love :)

Shot peening is a common thing to do to extend their life, and what I will be doing
Pete
Thanks Pete, I will ask around to find a shop which can do this. The place I'm bringing the head might be able to. Otherwise it will be a fun time finding a place. I appreciate the suggestion, I was about to think I could use them as-is.

Hi there, in your pictures of 6 pistons, on the top of the dome of pistons 4, 5, 6 is there a number that's something along the lines of 7222? If so they are Borgo 10.4's. Those three look like it anyway, from that picture anyway.
Top surfaces were bare with no markings before cleaning. They look identical to the other ones (pictures aren't clear) in height, only visual difference is that small ring of material removed from them. Not sure what to make of this.

@stevespiderguy , If this has already been mentioned, I apologize. Measuring the liners at the indicated spots, measuring for taper and out of round can be brain numbing. Looking for the maximum taper and out of round of .0004" makes me cross-eyed. If I am considering reusing the P&L's, I just measure the piston to liner clearance with long feeler gauges. You can buy a set ( 11'' long, .0015" to .040" ) on Amazon for less than $20. The (Alfa) Factory Engine Overhaul Manual gives a piston to liner clearance of .0016" - .0023". I have rebuilt street engines with as much as .004" with no issues. Be sure to check the fit of the pin and pin bore in the pistons, too. As for the rods, I always replace the small end bushings (give the machine shop the piston pins and they will size - hone the bushing to fit properly). My machine shop guy also (as a matter of course) takes a thousand or two off the big end cap and then rebores the big end to spec. He says that they all get "ovalated" and this makes the big end round (and to spec) again. If the Forum has Publication PA8777 ENGINE OVERHAUL MANUAL, read it. It's a wealth of information.
The shop that cleaned my liners said they measured in spec, I think I'll double check this anyway. I'm not home so I can't check my overhaul manual (at least I think I have the factory manual), is this .0016" - .0023" on both sides or do I put the piston touching the liner wall on one side and measure clearance on the other?

Good idea on the small end bushing, the shop I brought the bottom end to can do this - I'm still looking over the parts to order so that's a little into the future. Regarding the big end, if you take a couple thou of the big end how is it re-bored to spec? Wouldn't it then be oversize as material has been removed?
 

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Discussion Starter #65
I'm working now on locating all of the parts I will need. The cart I have assembled is attached. I will need to check with Paul about adding Viton seals, and verify I will have the seals for mating the SPICA pump. I also need to identify the appropriate piston ring set for OEM 9:1 pistons, which I may need to get from Classic Alfa or Centerline. Currently I cannot locate a water pump for a 2L SPICA car - I understand it is good practice to replace, can anyone comment on possible source?

Thinking out loud, I will also be sourcing all new sensors for good measure, and will have the radiator re-cored and install an electric fan.

Once this plan is finalized, I will bring the head to a shop and have valves + seals replaced, and seats re-ground. Then I will check valve clearance with feeler gauges, order correct tappets from Spruell Motorsport or Centerline, and replace tappets myself. In this way I have an experienced professional do the seating but I will do the time consuming clearance adjustment. Edit: I will also bring conn rods to be shot peened and have small end bushings replaced at this time.

While I wait for the top end to be done I will be able to assemble the bottom end with the soothing voice of Bob Seger. By the way, my torque wrenches were each $20 from Harbor Freight. Can anyone comment, do I need one of them $40M Snap-On torque wrenches for engine work?
 

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@stevespiderguy , Measure piston in sleeve with one feeler gauge on the skirt side. Measure at several places along where the piston travels. A small amount of material is removed from the rod cap, and also the mating surface(s) of the rod where the cap attaches. This makes the circle smaller. Machine shop then bores the circle to spec. Yes, this then makes the stroke a few thousands shorter, but ensures that the big end is perfect.
 

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Discussion Starter #68
@vintagemilano Upon close inspection, VERY difficult to render the text on the top of the pistons in question, labeled 4,5,6 in the photos I posted recently. They say "035->" (-> is an arrow pointing to the right). Regarding the torque wrench, my old engineer brain wished to find some concrete table of comparisons, though videos and Chevy forum comments seem to show Harbor Freight's new Icon line gets great reviews for accuracy comparable to Snap-On. I will do a bit more reading but probably will end up getting one of those in 1/2". I have their cheaper Pittsburgh line, I'd just go get them calibrated, but I expect to spend the same as the cost of getting an Icon, so for now it seems a sound investment.

@andylarry I found and ordered one of these, will check clearance and pistons when it arrives then go from there.

Almost forgot, in my list of parts in this post, forgot to mention I will be getting one of Paul's improved guibos with steel reinforcement plates. This will complete the total overhaul of my drivetrain (except the rear diff, still WIP as it's cold out and with all this isolation, haven't yet found the resolve to go to my parts garage to grab this and the steering box). Both will be overhauled and replaced as well. Then I'll have an [entirely] new drivetrain [less the gearbox]. It performs well except popping out in reverse if not gentle, so to keep focused on all that I'm doing now I'll reserve this for future work. I could just open up the one from the project car and consider swapping in as-is, but it's untested and I am not 100% confident in the original mileage of 70k being accurate. I'm getting off task here, so I will create a separate thread so as not to de-rail my own engine overhaul thread.
 

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Be aware that the instructions with the Giubo plates may be wrong, It took me several attempts to get the right number of washers in the right places. It was documented in a thread a nfew years ago,
 

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You don't have to shot peen the connecting rods, just a suggestion ...

Pete
 

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Discussion Starter #72
Thanks for sharing those pictures. Here are some close-up pictures of the pistons I have, you can see the "035->" printed on the top (piston 5). The comparison images show the two shapes next to each other - they appear identical except for the slight cut out section. I tried taking a picture of the text on a piston from the Spider engine (piston 1), it's barely legible but seems to also be printed with "035->"

Masses of candidate pistons:
  1. 441.47g
  2. 443.18g
  3. 443.24g
  4. 443.87g
Diameters of candidate pistons:
  1. 3.3041"
  2. 3.3044"
  3. 3.3047"
  4. 3.3046"
It seems they are slightly out of spec. Piston diameter spec for Class A (Blue) according to the engine overhaul manual is to be 3.3045-3.3049in. Is 0.0004" under a deal breaker? Or the total range of mass being 2.4g? Maybe for the mass I could shave a thou off the bottom of the highest mass piston to bring it into spec...

@PSk I looked into it and I agree it's a good idea. The price of a Carillo rod set motivates taking proper care of these rods... I'm learning quickly to take care of what I've got here.
 

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