TEA20 re-build

kaesark

Member
Need some advice please, recently picked up 1953 TEA20, was told that previous owner had run without oil after putting hole in sump and crank had gone through sump as well.
So I pull off sump and take head off and discover crank is intact and motor has not seized as able to turn crank over with pistons moving freely with valves also.
There is no doubt the head will need some attention as looks black as I will pull pistons out tomorrow but tops don,t look too bad just some carbon on top, the bores look OK but I'm a novice so may need new sleeves and I suspect new rings. How can I tell if the crank shaft needs new bearings or is this a job for the engine re conditioner to determine can they test the crankshaft while its still in place or do I need to remove from block.
Wow sorry for burbling on.
 
Were this tractor mine and noting that you were lied to about some items, I'd buy some plastiguage, remove the cap and lower bearing from one rod and one main bearing and use the plastiguage to determine the wear or damage to the bearings. If the bearings look good and are within specications for wear I would replace the sump, put in good oil and run it. The engine may use some oil so keep checking the oil level until you are sure you know how often it needs oil added. Unless you expect to use this for heavy field work that engine may not need any more than that.
 
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Plastigauge used on the number one bearing with an old , then new bearing . This is done from under the tractor with only the sump and oil pump off .

This is what you will see of the crank bearing running face when looking upwards.
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I forgot to mention that the new bearing I ordered were defective , under the specified size and so showed even greater clearance than the 50 year old worn ones ! Never just assume that new parts are correct or ' better ' than the old ones .
 
You can usually tell if it was damaged from lack of oil. While the pan is off, pull each main cap, one at a time, look at the bearing and crank surface. A damaged bearing will show signs of heat discoloration, melted/galling on the surface of the bearing or soft stuck to the crank surface. Also the tabs that locate the bearing should be in good condition and the bearing has not spun in the bore.

Do the same for the rod bearings, inspect them one at a time, keeping the cap with it's mating rod, back on the same direction it came off.

If all looks good, before final reassembly, get some Plasti-gauge to check the actual clearance.

A shop manual will be a valuable investment. It will give the clearances and torque values.

As for the head needing to come off, the only real way to know is to run a compression test, get it running and see if there are overheating problems. I assume the black you see is in the ports? Doesn't tell anything about the head, that is more a carburation problem or oil consumption.
 
Service Manual is a must:

Here are several pics. of a TEA 20....Service manual is a must:

Torque, clearances, procedures for installing components......Service manual is a must:

Proper orientation of connecting rod assemblies etc. etc. "who says they were installed correctly last overhaul"........Service manual is a must:

Tooling for holding LINERS in place.......See pics.
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The Governor weights were ready to fall off/detach from the holding pins. Chain, Sprockets, Governor ,Gaskets, Front oil seal were replaced at sometime in 1967> 1969 when a MAJOR was done to the ENGINE. I rotated the crankshaft CW/CCW and noticed 4 TEETH on the FLYWHEEL had to move before the DISTRIBUTOR ROTOR would move. Now only one tooth on the flywheel will pass before the Rotor moves. The governor was sticking at full throttle and would not idle down.

Info I compiled when REPLACING Crank sprocket ,Camsprocket and Timing Chain.
(1) 85 MM Bore Engine:

(2) Front Lip Oil Seal "National /Federal Mogul Lip Seal" # 472164V A SMALL amount of BLUE Silicone was placed around the inside bore of the front timing chain cover before Lip seal was installed:

(3) I installed a repair SLEEVE on the front drive Pulley, make "DURA SLEEVE" # 99175. The sealing area were the LIP SEAL makes contact was slightly grooved. Dura Sleeve specs. 1.745">1.753" Diam. # 68 Rockwell Hardness:

(4) On installation the Governor plunger shall be reseeded tight against the Flyweights and no weights shall be loose or hanging down:

(5) A small amount (only enough to make the surface shiny) of engine oil was added to the shaft of the governor PLUNGER as well as the timing chain:

(6)There are NO timing MARKES on the NEW Sprockets. You may whish to line the timing marks up (facing each other) before you remove the sprockets:

(7)Place the old sprocket (CAM SPROCKET) on top of the new sprockets and accurately scribe the new sprockets as to the timing marks. There are FOUR hols in the hub of the CAM SPROCKET. Keeping turning the old sprocket until the four hols and all teeth line up. These hols are slightly off set. I used several SHOULDERED cap screws to ensure I had the new and old sprockets properly aligned. You may have to flip the old sprocket over...see right up:

(8) It's good practise to measure the thickness of the hub of the old crankshaft sprocket and the new crankshaft sprocket as the teeth on the two sprockets should align for both proper operation and longevity.(there were shims between the old Crankshaft sprocket and the shoulder portion of the crankshaft):

Cheers
Bob...
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At first I thought you were line boring with that drill on steroids- what is going on? Yeah, no timing marks.. pommie engineering at its worst...
 
QUOTE...At first I thought you were line boring with that drill on steroids- what is going on?

Hi Tony in Mass........I had access to a 3/4 " AIR DRILL........cranked the air up until engine RPM was such that OIL PSI registered on Gauge...Verified OIL to TOP END...........it's a Canadian thing.............:)

Bob........
 

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