Rebuilt, need help for requirements

[sagaboy]

On behalf of my friend after taking note of http://www.shoptalkforums.com/viewtopic ... 8&t=140623 he decided to have his just bought 1972 1.2 engine rebuilt and also based on asking the previous owner saying that he did nothing to the engine for the last 10 years (that's as far as it went).

My friend is seeking some advise on what parts that MUST be replace with NEW the reason is that he depend on the "under the tree" mechanic to decide and he wants to have his options and NOT solely on the mechanic opinions. He would like to say "thanks" to everyone for the input and will appreciate it very much.

[doc]

Really need to know more, but, just to start the thinking:

A very basic rebuild of the engine will be:

The 1200 is way back there and upgrades will be worth considering, like to the more modern and commonly available 1600. But, if rebuild on the cheap is the order of the day, then start by disassembling engine completely to find out where you are. The case will likely have to be machined (line bore and thrust cut on the first bearing). The crankshaft may need work. Have machinist check out rods and, if acceptable, replace the rod bearings with correct oversize. Measure pistons and cylinders to see if they can be reused - if so, hone and re-ring. If not, new P & C kit. Have the machine shop do a valve job on the heads, inspecting valve guides and valves, if necessary. Inspect camshaft, rockers, lifters and pushrods for wear and replace/fix, as necessary. Fix all the other hang on the engine stuff - tin, fan, gen, fuel pump, oil pump, etc. Replace all gaskets and seals. Reassemble. A Bentley manual is invalueable. Muir's book will work in a pinch.

This is about as cheap as one can do and expect engine to perform well and last a while. The machining work is fairly common at the basic level, but critically important that it be done by a decent machinist. Cost expectations, I guess, would be $500 - $1000US.

I built a motor just about like this a few years ago and I know it is still running. This isn't the really recommended method, but would probably work out with careful attention to detail.

Good luck,

doc

[sagaboy]

Doc, thank you for the information, it is appreciated.
I will forward the info to my friend, the 75 years old "under the tree" mechanic has been doing nothing but rebuilding, servicing and repairing VW for the last 35 years and just need an extra pair of brains, eyes and we will be helping him do the rebuilt.
Yes, we have both the manual "Bentley & Muir's".
Yes, his quoted price is "Max" all change at US$1,500 or minimum requirements $800
Yes, we don't intend any upgrade, just re-built to as close as original as possible.

[doc]

Disassembly, very close measurement and the Bentley manual should point the right direction. Perhaps your man will know the best machinist to talk to.

Good luck.

doc

[Marc]

Is this a "D" case? What's the engine ID number? Does it have single or dual oil pressure relief valves?
Late 1200 cases are very similar to 1600 cases, and are often found to be in pristine condition internally (due to the relatively low stresses they've endured). Considering the limited availability of 1200 parts it might make sense to round up the other core parts required to build it bigger. With a 15/1600 crank & rods and a little extra machinework it could be done fairly easily...

[sagaboy]

Is this a "D" case? What's the engine ID number? Does it have single or dual oil pressure relief valves?
Late 1200 cases are very similar to 1600 cases, and are often found to be in pristine condition internally (due to the relatively low stresses they've endured). Considering the limited availability of 1200 parts it might make sense to round up the other core parts required to build it bigger. With a 15/1600 crank & rods and a little extra machinework it could be done fairly easily...

Will check-up on the engine ID?
Yes, its a dual oil pressure relief valves. Absolutely no intention to built it bigger. All new parts are still available over here, we check it up with the supplier before taking the engine apart.

[Marc]

OK. Be aware that there are two distinctly different types of 1200 cylinders - the classic ones are ~86.25mm O.D. where they plug into the case.
Some later 40HP cases are bored to 90mm (13/15/1600 dimension) - those take a special jug with an extra-thick spigot.

[sagaboy]

Is this a "D" case? What's the engine ID number? Does it have single or dual oil pressure relief valves?
Late 1200 cases are very similar to 1600 cases, and are often found to be in pristine condition internally (due to the relatively low stresses they've endured)...

The engine no. 0957089
Any special info on this engine?

[Marc]

D0957089 should be a `72, so it's probably the original. I've only seen a few late 1200s (they were never sold in the US) so can't offer many details. The last 1200s we got were in 1965; those 9xxxxxx motors were similar to the "D" (best 40HP heads, 1.1:1 rockers) but were of course based on early single-relief/small passage cases and were 6V.
His should have a 130-tooth, O-ring-seal flywheel with a 180mm clutch. That'll do for a 1200 or tame 1300, but if he needs a clutch and/or flywheel resurface anyway this might be a good time to put a 200mm flywheel on it - the clutch should then last approximately forever with a 1200.

[sagaboy]

D0957089 should be a `72, so it's probably the original. I've only seen a few late 1200s (they were never sold in the US) so can't offer many details. The last 1200s we got were in 1965; those 9xxxxxx motors were similar to the "D" (best 40HP heads, 1.1:1 rockers) but were of course based on early single-relief/small passage cases and were 6V.
His should have a 130-tooth, O-ring-seal flywheel with a 180mm clutch. That'll do for a 1200 or tame 1300, but if he needs a clutch and/or flywheel resurface anyway this might be a good time to put a 200mm flywheel on it - the clutch should then last approximately forever with a 1200.

Thanks, Marc. Next week, we are going to strip-down the engine and will check on your suggestions.