Eldorado Engine Rebuild

[scra99tch]

This will be my first ever rebuild so planning (not my strong point) will hopefully be fully completed before I start. 

Anyone know off the top of their head what 1st undersized measurement is?  Also difference between 1st undersized and 2nd undersized is?

Looking for a list of parts needed for an inside out engine rebuild.  Off hand   

Transmission also.

I'll do the leg work through one of the suppliers but I'm going to bed soon.

Thanks

 

[Hahnda]

I think the info you are looking for starts on page 30.

http://www.thisoldtractor.com/mg_manuals/workshop_manual_700_750.pdf

[Antietam Classic Cycle]

1st under:                                                   2nd under:
front main: 37.775 mm/1.4872"                   37.575 mm/1.4793"
rear main: 53.770 mm/2.1169"                    53.570 mm/2.1090"                 
crankpin: 43.729 mm/1.720"                        43.475 mm/1.710"
                          to                                                     to
               43.740 mm/1.722"                         43.486 mm/1.712"

List from a recent 850 GT engine rebuild:

- rocker cover gaskets, thick (2)               
- timing cover gasket                        
- head gaskets (2)                     
- base gaskets (2)                       
- oil pan gasket, thick                        
- breather pipe gasket                       
- rear main bearing flange gasket                 
- exhaust gaskets (2)                       
- intake manifold gaskets (4)                  
- distributor gasket                          
- oil pick-up gasket                        
- oil pipe gaskets (2)                      
- cylinder stud o-rings (12)                     
- front crankshaft seal                     
- rear crank seal                     
- flywheel bolt kit                        
- 8mm crush washers (6)                     
- 12mm crush washers (2)                         
- 20mm crush washers (3)                    
- Gilardoni cylinder kits (2)                                  
- rod bearing shells, 1st under (4)            
- front main bearing, 1st under                     
- rear main bearing, 1st under                        
- oil pump                              
- oil pump key                         
- intake valves (2)                     
- exhaust valves (2)                     
- valve guides (4)                     
- valve guide circlips (4)                     
- refaced lifters (4)                     
- timing chain                     
- timing chain tensioner                  
- rocker arm pins (4)                     
- sludge trap plug                     
- oil pressure sender                                                                       
- NGK BP6ES (2)                      
- distributor advance springs, pr.                
- distributor rotor                      
- condenser

May not be a complete list. This engine did not need rocker bushings and con-rod small end bushings.                         
                               

[Kiwi_Roy]

To give you a point of reference my Eldorado has done 130,000 miles, The bearings were right at the limit of wear but I just replaced the big end bearings.
Order a set of Giladoni cylinders with pistons
New Valves and valve guides
A complete gasket set
Overhaul kits for the carbs

Never mind Charlie is the guru, wot he sez

[chuck peterson]

Looking at that list, I think I've just decided NOT to rebuild that SP motor...that's all the "oh, yeah" stuff that nickels and dimes me to death

[scra99tch]

 Thanks a lot.  Exactly what I was looking for.  I'll measure out the crank and bearings.  And reuse what I can. 

Everything looks alright.  So may end up reusing some things.  As for the transmission that's apart and going to be a bear.

[Chuck in Indiana]

Thanks a lot.  Exactly what I was looking for.  I'll measure out the crank and bearings.  And reuse what I can. 

Everything looks alright.  So may end up reusing some things.  As for the transmission that's apart and going to be a bear.

What's wrong with the transmission?

[scra99tch]

Broken bolt in top for tapped holes, one looks like it was heli-coiled but does not function.  Just a fear of gears maybe and doing it right. 

No tools yet to pull front gear nut off, or pull bearings out. 

The usual.  This is really my first rebuild like this.  I will read up on this old tractor and maybe try to do my own rebuild blog.

[Chuck in Indiana]

Most people are afraid of transmissions until they get into them. They are just nuts and bolts, too. The Kid wanted me to walk him through building up his Spot transmission with new gears, bearings, etc. I told him it would be the blind leading the blind. When we opened it up, he said.. "Oh, I see how this works.. why was I worried?"  With Pete and John's help on thisoldtractor, you'll be able to do it, too.

[JoeW]

Anyone know off the top of their head what 1st undersized measurement is?  Also difference between 1st undersized and 2nd undersized is?

Are you making the assumption that you'll need under size bearings or, do you know you have a problem. Guzzi cranks are tough. Last year a tore down a rough 850 motor, the bearings were shot and the crank looked really bad. I ordered all new first under bearings and sent it off to the machine shop. He called a few days later and said the crank cleaned up in the acid bath and polished up just fine, standard bearings fit perfect.

Make sure to clean the sludge trap.

[Kiwi_Roy]

Most people are afraid of transmissions until they get into them. 

I resemble that remark, I was really hesitant but it comes apart in big chunks. I put it back much better than I found it, I must have had it apart 10 times before I was satisfied.

[Tom H]

The last time I did a Triumph trans I had it apart what seemed like 10 times to get it to shift correctly. 

Still need to try a Guzzi trans. One of these days?

Tom

[scra99tch]

Are you making the assumption that you'll need under size bearings or, do you know you have a problem. Guzzi cranks are tough. Last year a tore down a rough 850 motor, the bearings were shot and the crank looked really bad. I ordered all new first under bearings and sent it off to the machine shop. He called a few days later and said the crank cleaned up in the acid bath and polished up just fine, standard bearings fit perfect.

Make sure to clean the sludge trap.

Nah I do not see any heavy gouges, a quick measure with a caliper (not a micrometer) showed 2.125 on rear journal.  I figure thats probably within spec, and should just be polished.  I look into the manual a bit more as I go.  Polishing cranks are probably not expensive and may be able to do it myself with some emory cloth (again I'll look into it before I attempt). 

So barring any marks and gouges I should be good to go on original crank.  does have a bit of surface rust on counter weights though, thinking an acid bath would work just fine.  I covered the journals when I took it out with oil soaked rags.

[scra99tch]

Were the oil pumps updated at some point?  The drive gear does not have the extension past gear.  Does the bearing come with two cages or just one of roller bearings?  Its wide enough to fit two.  Also my outter race does not sit flush with the casting.

I can post pics if it helps. 

[scra99tch]

It looks like it original equipment and matches the one on MG cycles improved oil pump but not from a billet block.  Strange I guess.

So should there be 2 cages of roller bearings in there to even the load out?

[Chuck in Indiana]

It looks like it original equipment and matches the one on MG cycles improved oil pump but not from a billet block.  Strange I guess.

So should there be 2 cages of roller bearings in there to even the load out?

Yes.
Edit: Well, as far as I know at any rate.  I've never rebuilt a loop engine.

[scra99tch]

Found the second roller cage. 

As for bearing outer race sitting flush any ideas?  Figure it's not flush because it be a bear to remove.

[scra99tch]

Should I put the 1K cc in?  Or leave it as is?

[JoeW]

Should I put the 1K cc in?  Or leave it as is?

If you use the Gilardoni 88 mm kits, you'll have to change rocker arms. Whether you go bigger or not, I would have the crank balanced.

[scra99tch]

I'll be dropping my parts off at the vapor blasters this week or next hopefully.  Here is a short list of what needs it.

I don't want to blast the frame or any of the tins just yet in case they flash rust while I replensih some funds.  Which by the way will start dwindling slowly as my pinion is shot in the rear drive.

Engine Case
Engine Sump
Rear Drive Case
Rear Drive Sump
Timing Cover
Belt Cover (This come chromed from factory?)
Heads
Valve Covers
Exhaust Decorative Clamps (??)
Transmission

Anything else I am missing.

[Hahnda]

Sounds about right. I have had carbs and the intakes vapor blasted as well.

The belt cover would not have been chromed originally but you do see them and the valve covers sometimes chromed.

I really like vapor blasting.

[scra99tch]

Sounds about right. I have had carbs and the intakes vapor blasted as well.

The belt cover would not have been chromed originally but you do see them and the valve covers sometimes chromed.

I really like vapor blasting.

Here they are picture is a bit dark but they came out great.

[Rick4003]

 

[scra99tch]

This will be ongoing as I have many questions.

Anyone know if MG Cycles Seal Kit has all updated viton seals?  Some of them look like they are.

Also what are the main bearings made of?  Just plain aluminum?

[danedg]

The bearing shells will be an alloy not straight AU.

The kits are complete.

[Antietam Classic Cycle]

Anyone know if MG Cycles Seal Kit has all updated viton seals?  Some of them look like they are.

Brown ones are Viton, blue ones aren't.