Nina Barton wrote:
>
> If you have been on the list a year or so, I asked questions then about
> rebuilding an engine vs. having someone else do it. The answer came back
> resoundingly that I should do it myself. I have been pursuing this course
> and have picked up an earlyish MGB engine (pre air rail) and have been
> working on it so that when I blow another head gasket, I can swap the old
> engine out and put this freshly rebuilt one in the car. I have the block
> back from the machine shop, and it has been decked so that it's flat.
> The head will be skimmed too, however it is still at the machine shop,
> This discussion of geometry comes at a good time for me, as within the next
> month or so, I will be reassembling this new engine. What should I have
> the machine shop do to make sure the engine will be correct, and what
> should I check myself? Thanks in advance, and if you need more detail on
> what's been done with the engine, I will be happy to supply it.
> Nina
Your request should generate a lot of replies, here is my pennies worth,
all small things, but important...
CHECK that all swarf has been removed from the oilways, in the
crankshaft, block, and head. Use pipe-cleaners and a good airline.
Careful with the airline, they can kill....
File off all the burr-edges of machined faces, these can cause nasty and
deep cuts in human flesh.
Ensure swarf and OIL is removed from stud holes, or the stud 'bottoms'.
Oil left in can actually 'hydraulic' out the end, and crack the casting,
as the stud is screwed in. Locktite in the head studs with 'Locktite
Studlock', saves them coming out when you undo the head nuts.
Oil the studs on assemble on their plain section, to stop them rusting
up and causing serious problems on the next head removal. They swell up
to jamb in the hole!! ESPECIALLY on the thermostat housing's alloy
casing. Head studs are tempered steel, others are mild steel.
Do not ommit the gasket from the oil pump to block face. Oil leakage
here is like a faulty heart in you and I.
Fill all oilways with new oil, reduces the NO OIL PRESSURE on start up,
( see later.)
Roll the pushrods like you do a billiard que, to check if they are all
STRAIGHT.
Spin over the crankshaft as you torque up each bearing, big-end and
mains. Do them individually so you can pin-point any that appear TIGHT.
Investigate ASAP a tight bearing. Often a bit of dirt under the shell!!
Use STP mixed with oil to lubricate as you assemble, never build dry.
Lubricate the seal at the back end of the crank, or it will burn out in
seconds on starting the engine......
Lubricate the timing cover seal for the same reason.
Fill the oil pump up with STP, and the oil filter, again to reduce oil
pressure lag. Those first few minutes can make or RUIN the engine.
Do not forget the cam lobes and cam followers, put STP on their faces.
These get no oil until the oil comes out of the crank pins.
Use a little gasket glue on the head gasket, where they all leak. A very
THIN line both sides of the gasket usually works. The waterway between
the head and block here weeps, and runs down just above the starter.
This fault is on virtually ALL 'B' series ever made. ( Even the Diesel
versions.)
Spin the engine over before you start it on the ignition, top get oil
pressure. If none, investigate ASAP. I actually seem to rebuild most
engines that still have starting handles, a very useful item indeed.
Keep everything spotlessly clean, and you will do a real professional
job. ( Better than some 'remanufactured' engines some people sell.)
Use torque readings as often as you can. To guess can mean an engine
that self destructs later, usually at 80mph on a motorway, ( freeway) in
pouring rain........
Run it in properly, the old way was 50 miles at 30mph, 50 miles at
40mph, 50 miles at 50mph. Then not above 50mph for 500 miles. ***Change
the oil and filter at 500 miles. Then the next 500 miles as normal but
limited to a max of 60mph. Others will disagree, but.........
Use heat resistant engine lacquer, MG red ofcourse, or Leyland black if
an 18V... Nothing looks worse than a nice new engine with all its
(cheap) paint peeling off.
Neil.
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