TR4A Engine Rebuild

[LGFromage]

County pistons are made in Israel by King but if you check their website only pistons for small engine Triumphs are listed. I have just managed to obtain NOS +0.20 County pistons for my TR. Being of composite construction they look pretty robust and come with rings made by Grant of the US. I would be interested to see how they compare to Moss's current offerings.

 

Tim

[RogerH]

Today I decided to do a bit of cleaning up.

 

Disassembled the rocker shaft. The shaft has between 0.002 and 0.005" of wear at the rocker positions so a new shaft will be used.

The bushes in the rocker arms have minimal wear in them. I feel tempted to remove the bushes and re-insert then +/- 90 degrees rotated.

This will position the wear in one bush on the valve side of the arm. The other bush will have the wear on the push rod side. Whilst the pressure face at 6-o-clock will have new material. Any reason not to do this.

 

#3 conrod detachable bearing cap is quite well scored - the bearing moved and slid under the the upper bearing shell; never seen that before.

I have four con-rods from another engine that I may use rather than getting the scored rod repaired.

 

The oil filter is the original Purolator - how does the centre bolt come out of the bowl. It has a spring loaded base in it. Does it just pull out?

 

More tomorrow

 

Roger

[stuart]

There should be a clip holding the plate and spring on the bolt. They can be interesting to get back into place.

Stuart.

[RogerH]

Thank you Stuart - another challenge.

 

Does anybody know the colour of the oil filter bowl. What is left is a pastel/flat greeny colour.

 

Roger

[stuart]

Thank you Stuart - another challenge.

 

Does anybody know the colour of the oil filter bowl. What is left is a pastel/flat greeny colour.

 

Roger

Yes thats the colour. A search on here should bring up a recent thread about it. I think it was in the 2/3 forum.

Stuart.

[RogerH]

Hi Stuart,

google found it quickly http://www.tr-register.co.uk/forums/index.php?/topic/44252-oil-filter-bowl/ it sounds like Teal Green - courtesy of Don.

 

Roger

[DJF]

Hi Stuart,

google found it quickly http://www.tr-register.co.uk/forums/index.php?/topic/44252-oil-filter-bowl/ it sounds like Teal Green - courtesy of Don.

 

Roger

[DJF]

Hi Roger

Would be interested to know where you sourced the Teal Green paint when you eventually get it..... just started a body off restoration so not not quite ready yet!

Dave

[RogerH]

Will do.

 

Roger

[MikeF]

Small comment FWIW:

On engine/gearbox work and other projects which would involve major dismantling and remantling to get at parts on a completed car, I generally work on the "I never want to see the inside of this particular part of the car again" principal. This means while I have access I tend to change/refurb more than is strictly necessary especially the bits associated with any worn part as they are all of an age and likely to follow soon.

Doing it now on a bench will be a whole lot easier than when its all back in the car. The incremental cost need not be that great and is much less than the aggro a few years down the road.

 

Mike

[RogerH]

I was tidying the block up this morning in readiness for thorough cleaning and found that the centre offside head stud had snapped.

I didn't remove these and didn't realise there was a broken one.

Interestingly there was a 1/8" layer of black oxide particles on top of the remnant suggesting that it had broken not at removal but a long time ago.

Removing it is becoming interesting. I'm now making a jig to drill down the centre of the stud. Hopefully the threads will be OK. If not it will be a helicoil.

 

Between the two centre head studs (left and right) there is a strengthening bridge in the water jacket; this has a lovely crack down it's full length.

I would think the head and studs will hold this in place

 

More later.

 

Roger

Edited January 8, 2014 by RogerH

[RogerH]

Hi Folks,

the dreaded broken stud succumbed to my endevours.

 

I made a free hand centre hole in the stud to try and 'Easy Out' it - sadly my centre and the stud centre didn't quite coincide. As I opened the hole up it was clear that I was getting too close to one side. The 'Easy Out' was quite useless so after a few tentative attempts to turn it I stopped.

 

So I made the jig that I should have made in the begining.

Measuring the 10 stud holes gave me a precise location of the hole with the stud stub stuck solidly.

From this I made a plate bridging three holes with the dodgy one in the middle.

The studs are 1/2" diameter, so I made three 1/2" holes in the plate - see the first pic.

I then made a drill guide - apprx 1" long. This fitted into the 1/2" to hold the centre. Rather than going in with the finish diameter I chose to go up in sizes to bring the hole centre back on track. pic 2.

The core diameter of the 1/2UNC stud thread is 0.405" - so this became my finish size. I crept up on this in 1/32" steps.

When I got to the finish diameter it was then down to picking out the old thread - these stud threads are bloody tough.

 

Getting this little broken stud out took nearly all the day.

 

Roger

 

 

 

 

 

Edited January 8, 2014 by RogerH

[RogerH]

Blimey don;t things take a long time.

The engine parts are all back now - eventually - I think they were turning the lathe by hand.

 

Any way the parts all look good. Hopefully they will all fit together.

 

I have spent most of the day making the mandrel for fitting the rear crank oil seal. Thankfully I had a piece of 3.5" dia ali round bar laying about (as everybody has).

If anybody needs to borrow a mandrel for their build give me a shout.

Tomorrow I shall tidy up some more parts before the grand rebuild commences.

 

Roger

[Motorsport Mickey]

Err...Roger did you use the incorrect workshop manual dimension for the rear crank oil seal or the correct dimension as approved by Christian Marx ?

 

If you search his posts you'll see it posted, bet you've done it already.

 

Mick Richards

[RogerH]

aarrrrrrgggghhhhhhhhh

[2long]

Roger, your groan is making me nervous! Is there a way to tell if the rear crank oil seal dimension has been messed up, after the engine is back together? Would it leak profusely, in other words? My oil pressure is good and it runs fine, but I'm worried my engine rebuild was done wrong!

 

Dan

[Motorsport Mickey]

Dan,

 

The good news is if it ain't leaking and you've done more than 500 miles I should imagine it's ok.

 

The oil scroll obviously only works when the crank is turning, literally screwing the oil back up the crank away from the rear mains and clutch area. The rear seal fits very closely (but not touching) to the rear crank area and scroll of the crank and scrapes the oil off the crank surface.

This only works when the crank is turning and so you may expect that over time you may develop an occasional "weep" from the rear mains when the car is stood as the oil finds its way between the non turning crank and the scroll alloy rear seal. Christian Marx's rear lip oil seal gives the best chance of stopping that because it can be fitted along with the original scroll seal (two are mostly better than one) and hence will combat this.

 

There are threads which gives the dimensions for the new mandrel size which I found (type in rear mandrel), however I have not checked them.

 

Mick Richards

[2long]

Thanks Mick: I elected to go with the original scroll seal rather than the modified, just 'cause mine is an early 2 and I'm trying to keep everything as close to the workshop manual as I can. I don't mind a bit of weep, as long as it isn't "cry me a river".

 

Dan

[stuart]

FWIW I have one of Christians Mandrels available for cheap hire.

Stuart.

Edited February 26, 2014 by stuart

[RogerH]

Hi Dan,

I couldn't find Christians post on the forum so I googled it and up popped 100's of hits on it.

Christians mandrel is fractionally smaller than the workshop mandrel, so a ST mandrel could easily be modified to suit.

 

I machined a mandrel to the ST figures but this afternoon it will be modified.

 

Roger

 

 

[RogerH]

Having modified the mandrel I proceeded (in a northerly direction) to fit the crank.

The crank rear bearing & cap fitted very easily. Stuffed the seal into the grove - having removed the two rear seal bolts that get in the way.

The front cap went on nicely. (more on this in a minute).

 

The centre cap just popped on. I then realised I hadn't fitted the bearing shell. Off with the cap. Fit shell; and the cap not longer fits over the crank!!!.

With the centre cap aligned with the casting below it the cap would not fit. Turn the cap around, and now the cap is displaced forwards by about 1.8" but the cap fits - and as they say "if the cap fits.........

Next step (actually this should have been the first step - fit the blanking plugs in the crank webs, The middle two were easy, in fact dead easy or possibly easier.

The rear one was interesting but there was enough room to get the allen key in.

The front plug hole was hidden from sight - bu99er - off with the front bridge bar, fit the plug, fit front bridge bar.

This is getting like some old fashion dance - two steps forward, one step back, bash thumb with hammer.

 

If anybody is concentrating you will have noticed I haven't mentioned the thrust washers - thankfully I did fit them.

 

With all the caps torqued down the crank still rotated freely - phew.

 

On with the sump cover temporarily whilst I do things at the other end.

 

Tomorrow I shall be doing things at the other end.

 

Isn't Welseal wonderful stuff. A little dab gets everywhere - nose, ears, hair and some on the engine.

 

Roger

Edited February 26, 2014 by RogerH

[graeme]

 

If anybody is concentrating you will have noticed I haven't mentioned the thrust washers - thankfully I did fit them.

 

Roger

 

 

Hi Roger,

 

Are the thrusts in the right way round??

 

Cheers

 

Graeme

Edited February 27, 2014 by graeme

[TR 2100]

Roger,

 

Some years ago, I was re-building my TR4 engine (in Hong Kong)

and followed pretty much the same routine as you.

As you say, Wellseal gets everywhere, especially when you soak

the felt in it first, then ram it into the grooves with a shaped drift.

 

Unfortunately, I DID end up with more than a weeping of oil from

the rear bearing into the clutch area.

Somewhat more than marking territory.

And the drives of friends are not my TRs territory anyway!

 

What I always wondered was (and maybe you can tell me with

your engine assesbly in progress) - Is is possible with the engine

upside down, for excess Wellseal to find its way to the bearing-to

-sump drain, partially blocking it, restricting the flow of oil back i

nto the sump.

 

Or maybe I just didnt get the real seal properly aligned!

 

AlanR

[RogerH]

Hi Graeme,

the thrust washer have their bearing surface (grey colour) against the crank. So I think that is correct.

They even have the correct gap; o,oo4" feeler goes in but a 0.006" doesn;t.

 

Roger

[RogerH]

Hi Alan,

there are two oil drains on the rear bearing/seal assembly that drain oil back into the sump.

The obvious one is the BIG tube forward of the ali split plate. This ducts the oil from the scroll under normal conditions.

The less obvious is a small hole in the Ali split plate near the flywheel end of the plate. This runs into a very small tube next to the BIG one. If excess sealant is used this could easily get blocked. Also the hole in the ali plate and the small tube are not in direct alignment so if you took the sump off with the view to passing a wire through it it may not clean it.

 

Roger