sprint eng rebuild

[xvivalve]

but my hobby could easily have become a business.

...and that is when it ceases to be a hobby and certain enjoyment is lost.

The past is littered with names who went this route but being too marque and model specific was often the downfall...

But then again, niche engineering is about all we have left...

[trackerjack]

Yes this is so true no training, youngsters that know nothing but being lippy and a manufacturing base that is disregarded by all, everything brought in from China................hang on I have heard that before

[trackerjack]

Even more methods of sorting the W/P clearance.
Clocking in TDC using a dial test indicator.



Flywheel was balanced on crank and is also on TDC.



Grease the water pump before fitting, failure to do this will result in the famous stuck water pump in block thread.



Using all gaskets in the set a little piece of plasticene is wrapped in selotape and placed on the waterpump bolt (this is my method)




like this and then put on the cover



tightened down securely.



measure the squished gauge and take away the thickness of gaskets to achieve .010"-.025" running clearance, too tight will strain the jackshaft too loose will cause mesh problems with skew gears, both wreck jackshaft and hence engine.I think mechanics have not given enough care to this important piece from day 1.


After setting pump try turning the jackshaft by hand and it should be free and smooth. The shaft in this block is a very nice fit and not sloppy as some are in high mileage engines.

I run an electric fuel pump so this is a blanking plate that I make to cover the redundant hole.

[trackerjack]

As an extra I would add that I oil freely all moving parts before assembly and the water pump has a reservoir of oil in the lower bush if its a new block or a total rebuild fill it with oil.as all these little places take a few seconds to reach on startup, which is the time most damage is done.
Of course the method I have shown does work but if you are an angler just put a tiny piece of lead on top of the W/P bolt, it squashes just as well.
Are you all bored yet ?

[triple tango]

all these little places take a few seconds to reach on startup, which is the time most damage is done.

I dont fit distributor, then before start up I fit a small socket & 1/4 drive extension to hexagon oil drive, then drive oil pump with an electric drill for several minutes.

[Jon Tilson]

Good idea but its also a good one to spin on starter plugs out too....just in case some of those holes in rotating parts weren't lined up to allow oil through....especially true of sprint rocker gear...

Jonners

[trackerjack]

Liking your ideas and they will be adopted especially as i always have cam lube spread on the cam as insurance.

[triple tango]

I got my drill to hold a steady 80 - 90psi showing on oil gauge. Perfect when you have an oil cooler to fill aswell.
Drill got a bit hot though ! Just remember to switch "hammer action" off

[newguy]

I think we are anything but bored its great to see an engine been built up so nicely.

[Carl]

I do both the Roy and Jonners methods. After re-assembly I spin the oil pump with a drill AND rotate the engine using a socket and bar on the crank pulley nut at the same time until oil starts coming out of the rockers. The first thing you see is the timing chain coming around wet with oil which means that it has gone right round the crank and is starting to make its way up to the head. It can take a while for oil to start dribbling out of the rockers on a rebuilt engine because it has to fill the rocker shaft first.

Really nice work Jon

[trackerjack]

I do both the Roy and Jonners methods. After re-assembly I spin the oil pump with a drill AND rotate the engine using a socket and bar on the crank pulley nut at the same time until oil starts coming out of the rockers. The first thing you see is the timing chain coming around wet with oil which means that it has gone right round the crank and is starting to make its way up to the head. It can take a while for oil to start dribbling out of the rockers on a rebuilt engine because it has to fill the rocker shaft first.

Really nice work Jon

Thanks Carl did you spot your lone piston in no 2 look its waving at you.

I think I am cracking up

[trackerjack]

Here is an inlet port that I have lightly attacked with a Dremel and flap wheel, Davw Walker of CCC fame stated that the Sprint head looked OK and the fact that it dropped down into the engine would be good for performance, well he has loads more experience than I and also Bill Blydenstein claimed that the 6 mm either side of a valve seat was the most critical and that heads flow better once there is a layer of soot on them. In view of this I have opted for a bit of valve gas flowing as shown 3 million years ago by Dave Vizard and more recently I see Dave Powell does a similar thing.



A virgin inlet valve.



A virgin exhaust valve.



After a bit of work using a drill press and Dremel



Inlet looks like this as the gas has to low across the top and in the top is curved and polished.



The exhaust has to flow the other way so the bottom is radiused to aid gas flow.



My TR5 had these mods in the early 80,s as did my Stag and they both flew, the Stag in particular lapped Goodwood in 1 min 44 and was even mentioned in MG magazine "Safety Fast" as I blew their MGC,s into the weeds, so they said they were impressed by the rapid Stag, I also owned an MGBGTV8 but this car could not go as fast as the basically standard Stag.

[trackerjack]

I have time but not much money, I need a vernier camshaft sprocket and I am an engineer , simple use time make sprocket and save some money and get the job done properly too



Here I am using a Kent degree wheel and pointer to establish TDC


If your eyes are better than mine the instructions are on the wheel to follow how to time the cam in.

[newguy]

Jon that looks really nice.

[Lewis]

Awesome thread! Hope to do similar some day!

Keep at it!