Finally started to assemble 2.0L

[tshih]

Hi All,

Just finished removing the old main bearings and installed new ARP rod bolts and rod bearings onto the crankshaft of the 1975 2.0L engine being rebuilt from complete strip down and cleaning.

Question 1. instructions say torque bolts with assembly lube 3X at 40ft-lbs. Measure stretch at 0.048-0.052". I didn't notice any stretch remained at 6.00cm before and after torqueing. Can one over-torque these ARP bolts?

Question 2. I have new Euro 2.0 pistons and cylinders to install and intend to weigh each piston/rings and balance them to the rods (which weigh 788.2 gm, 788.3gm, 789.4gm and 787.7gm).
How would the expert builder match the piston weights to these rods? Heaviest pistons to lightest rods so all combinations are as equal along the crank as possible?

Question 3. Forgot to make a checklist for what items needed to go back into case before sealing halves together with locktite 574.
should I disturb the original case plugs or leave them alone?

I remember to insert new cam with new standard cam bearings, oil sump baffle, time the cam to crank, new main bearings, what else am I forgetting?

[tshih]

Just weighed the pistons and wrist pins and their weights are 723.10grams, 723.33 gm, 723.84 gm, and 722.96gm. Pretty close grouping (I'm impressed by Mahle for having such tight tolerances)!.

[tshih]

Also, in setting up the oil control ring gap, do I position the oil ring gap at the top of the engine or at the bottom of the engine inside each cylinder? I will be positioning the other 2 rings' gap at 120 degrees offset from the oil control ring gap. Any better suggestions?

[Bleyseng]

top of the Piston.

Whoops, I misread you last post as I thought you were talking about where to place the rings to measure the ring gap.

[tshih]

Bleyseng,
thanks for the reply. Any reason for the bottom position? One could rationalize that as the engine sits and the oil drains off the walls of the cylinder it would pool into the gap if it was on the bottom and during next startup more oil will be spread onto the walls to promote better lubrication.

[tshih]

Bleyseng,

What are you saying?

[Bleyseng]

When you measure and set the new rings gap you install the ring at the bottom of the cylinder and use a feeler gauge to measure it. You must set the ring gap or check it as the rings come big so you can set it properly. don't assume its right and just install it!

"Also, in setting up the oil control ring gap, do I position the oil ring gap at the top of the engine or at the bottom of the engine inside each cylinder? I will be positioning the other 2 rings' gap at 120 degrees offset from the oil control ring gap.

set the oil ring gap at the top of the piston.....

[tshih]

Bleyseng,

I'm using new Mahle pistons and cylinders and hence rings are already installed when they come as a set in the box. I just took each one apart to weigh the pistons and replace them together with the ring gap repositioned as per question.

I assume from the 914club advice that I am to bring the crank, rods, and flywheel to the machinist for proper sizing of the rods and bearings. Do I bring the wrist pins as well?

[Bleyseng]

Yes, bring the wrist pins in too as small end bushing need to be sized for the wrist pins (reamed).
You should have the rotating parts balanced too.

You still need to remove the rings and check the ring gaps!!! don't depend on some moron to do this right. Always check everything!!!!

When you install the cylinders over the pistons is when you align the rings gaps as you first install all the pistons cuz its really hard to install the keepers with the cylinders attached.

[tshih]

I assume checking the rings mean pressing them together and measure the gap while the rings are still in their grooves with a feeler gauge. What should they be (do you have the specs for 2.0L Euro pistons? What if they're too large (get other sizes?-I don't understand what I can do if the moron who shipped these NEW matched sets of P/C from Mahle got it wrong.)

[Dave at Pelican Parts]

I believe that checking the ring gaps is done by removing the rings from the pistons, then putting them into the cylinder bore. Traditionally, you use the top of the piston to push them down into the cylinder, but that's not strictly necessary. Put them down toward the bottom of their "natural" travel, and make sure they're parallel with the end of the cylinder. (Assuming the end of the cylinder is true!!) Then you use a feeler gauge in the ring gap to see what the gap is. Figure out how much you need to file off (if any) to get to the spec'ed gap, pull the ring out, file, re-check, repeat.

--DD

[Bleyseng]

normally, its the job of the engine assembler to gap the rings or atleast double check what some other moron has done. Don't assume anything when it comes to engine building as for sure that is where it will go wrong.

BTDT

I measure the rings about a 1 inch from the bottom of the cylinder using a piston to center in the bore. Measure with feeler gauges to verify the gap or remove and carefully file it to the correct gap.

[tshih]

OK, when do rings break? When the gap is too small or too big?

[Bleyseng]

When the gap is too big, oil will slip by as the rings don't have enough tension to the cylinder.
When the gap is too small they can break as there is no enough room for them to expand or they expand and the engine can freeze up.

Carefully check the rings and gap them per the specs.

[tshih]

I only have specs from Haynes manual. Anyone have factory manual to posts for 2.0L European compression pistons/cylinders.

Thanks in advance,
Tom

[Bleyseng]

use the Haynes manual specs as they should be fine.

[Bleyseng]

how about this service?

[tshih]

Much obliged Bleyseng!

Tom