Engine out / one problem after another

[Adrian]

Hello Chaps

 

Further to the sump gasket possible insitu installation, manifold refurb, etc. I've taken the plunge and decided to remove the engine - this will also allow a better clean-up of the engine bay.

 

I've started to strip the engine ancillaries. Firstly would you re-use bolts, nuts studs, etc, even if nuts are seized on studs (so the stud removes).

 

Once the exhaust manifold was off I noticed some rust on one of the core plug - does this need replacing? Would you use an automotive adhesive when refitting?  

 

Also there seemed to be a fair bit of oil under the distributor - are there any seals that may be needed?

 

Jobs on the engine while out are - strip, clean, paint block

                                                     - clean and paint ancillaries where appropriate

                                                     - new sealing block

                                                     - gaskets for water pump, timing chain housing, sump, etc

                                                     - new club LUCAS distributor with electronic ignition 

                                                     - new water hoses / stainless overflow system etc

 

That's roughly it along with some seals for the flywheel shaft if needed.

 

The rocker cover isn't too bad but if it was to be re-painted what would you use?

 

Thanks

 

Adrian

[Pete Lewis]

yes change all the core plugs,  always been fit them dry they need to grip, if you use a sealer dont use  a slippy silcone 

 

something like wellseal would be better  smells nice too.

 

the dizzy  base  has an 0 ring

 

rocker paint, club sell rattle can of orig gold , but any colour , body colour , black ,  whatever takes your liking

 

if the stud holes are dented/sunken  knock it back with a hammer and drift 

 

same with the sump , always clout the holes back  to remove deformed flanges .

[Adrian]

Thanks Pete - so is that all the core plugs in the block?

 

Also can you tell me is the back plate (photo) strong enough to bolt onto an engine stand? If not where would the fixing points be?

 

Thanks

 

[JohnD]

That core plug has been weeping!  Must change!    Some use a smear of an epoxy glue to promote sealing.   Install by selecting the biggest socket that will fit inside the cup, and whack it in with a BFH!

 

As an aside, the Americans persist in calling them "freeze plugs" this give the impression that if the engine freezes, they pop out and save the block.  They won't.  To compromise the other name is a "Welch" plug, I presume after the inventor.

 

Re-using bolts and studs.    Yes, if not "mission critical"!    I always fit new head studs and nuts, AND the hardened steel washers under them, and never reuse Nyloks - you can but they aren't costly.    A pack of new Nylok nuts in various sizes isn't expensive: https://www.toolstation.com/shop/p60090?mkwid=sXNDfx6kc_dc&pcrid=142501343890&pkw=&pmt=&product=60090&gclid=Cj0KEQjwkZfLBRCzg-69tJy84N8BEiQA  But that particular pack has some rather big ones!  Others are available, or buy them in bags of 20 or so.    7/16", 1/2", 3/8" and 5/16" should do it, 1/4" and 3/8" if your feeling rich.

 

But not if they are seized.    The usual place this happens is the exhaust manifold.    When you rebuild, use Silicon bronze nuts as these will not seize.  Available from marine suppliers.

 

All the usual Triumph suspects suppliers will sell you a complete set of gaskets for a rebuild complete with those little wooden wedges for the bridge piece (sealing block?)

 

The Flywheel shaft is the rear of the crankshaft, and unless you have a very early engine, the seal sits in its own housing on the back of the block.

 

Do you plan to fit new piston rings?   Not a bad idea since you're going this far anyway.  But check that the bore isn't worn.  Is there a lip at the top, wher the old rings couldn't reach?    If there is then new, unworn rings will hit that, and can shatter.    You used to be able to get chamfered top rings to clear the lip, but that's a bodge, really.  If the bore is that worn, the you must consider a rebore and outsized pistons - yes, I know the cost is rising.  A machine shop can tell you if the lip alone can be bored out, so you can fit the old pistons and new rings.

If there is no lip, then new rings but first Hone the bore, make cris-cross scratches on the bore walls, to hold oil and lubricate the new rings as they bed in.   Your machine shop can do that, or you can buy honing tools, either three rotor or brush style.    

 

Sorry, gone on a bit!

Good luck!

John

[JohnD]

I use a back plate to mount the engine on the stand, but I can use an old one I'll never use again.

I do so, because the stand only uses four bolts, and they must go into the same holes on the back of the block, where eight hold the plate on.

And, I have cut out the hole in the middle, so that I can install the rear oil seal with the engine still on the stand.

 

 

 

An alternative is to mount it to the front engine mount lug - O-oh on a six cylinder - you have a four?

 

Another alternative is to make your own dummy back plate from a sheet of 4-6mm steel.  Use the original as the pattern and bolt that in place of the original.  Then you can place your stand bolts - and nice big ones too!  - wherever you like on the dummy.    Bolt the stand spider to the back plate, dummy or not, and then slide the spider onto the stand - its easier than the other way!

 

JOhn

[Clive]

At that stage it would be foolish not to check main, big engine and thrust bearings. The sump will probably need a good clean out if not recently done, but will be obvious. Oil pump worth checking, and likely to be fine (90% certain better than the new repro pumps which are often outside tolerances out of the box)

[Pete Lewis]

and check the rear cam bearing bore these can wear and you get everlasting tappet noise which isnt tappets

 

the dizzy pedestal is sealed with a gasket , there are various thickness to adjust the drive end float

 

Pete

[Adrian]

Ok I'm taking this slowly, I'm waiting for the correct 5/16 bolts to arrive to put it on the stand (bolting into the block). In the mean time I've taken off the timing cover and found grooves on the tensioner and approx 11.5mm play on the chain. As I have to take the sprockets off to get to the sealing block I assume I should change both as the chain is close to the Haynes manual 13mm limit.

 

What play do you normally get on a new chain? Any suggestions for decent quality tensioner suppliers or are they much of a muchness?

 

Never thought I'd be going this deep!

 

Cheers

[Pete Lewis]

There are some better makes of chain ,english or german seem favoured the tensioner groves is normal, any replacement will end up the same

silliest job is getting the small slpit pin replaced

 

and to fit a new chain you need a acurate way of determining crank and cam lobe tdc point

 

a simple piston stop on the block , turn piston to it in both directions and with a simple protractor

(Card disc ) mark the two points , halve this for exact tdc of the piston

you really need a dial indicator to do similar on the cam, turn a lobe to a decided lift on the dti do this both sides of the lobe again simple card disc attatched mark the same rise and fall points

mark halves between the marks that the tdc of the cam lobe

 

dont turn anything ang assy the chain and sprocket, the sprocket has off set holes that give 1/4 tooth increments buy switching holes and turning it over

 

this all sounds a pain but read the manuals and practice its the best way of getting the cam timing really spot on

 

pete

[Waynebaby]

Adrian,

 

If you are thinking of delving into the valve timing side of things, there is a useful article in the May 2016 issue of Practical Classics which describes the methodology and maths needed to get the cam timing precisely right on a Triumph GT6.

 

Wayne 

[JohnD]

Adrian, Wayne,

I haven't read the Practical Classics article, but no maths necessary, absolutely none at all, to set the valve timing on a Triumph.

 

Use the "Equal lift on overlap" method.

 

I described if briefly here: http://sideways-technologies.co.uk/forums/index.php/topic/7538-crank-installed-backwards/?hl=%2Bequal+%2Blift&do=findComment&comment=99531  Post 8

 

Glad to go into more detail - not much needed! - if you want.

JOhn

[Waynebaby]

Thanks John,

 

Just goes to show that there are two ways to skin a cat. The PC article method needs a timing disk on the crank and knowledge of the actual cam timing periods but your technique (which I'd have known about if I read my WSM more thoroughly) is much less of a faff.

 

Wayne

[Pete Lewis]

cornflake packets can make useful discs.

 

Pete

[JohnD]

Wayne,

Hope you don't think I was misleading, but to do "Equal Lift", you do need to find true TDC.  

A timing wheel and a piston stop are best for that, so you do need to be able to note two angles, work out the difference between them and half of that, which isn't really "maths", more "Arithmetic"!

 

John

[Adrian]

Just trying to keep this to one thread. As you know I'm going slow. I'm at the crank shaft.

 

I haven't removed the timing sprockets yet - just looked in from the removed sump to inspect the big end bearings. Attached are the photos of the front bearing and the Journal. the others are similar. As you can see it is not a mirror finish.  Thoughts?

 

Also I've seen online videos showing people measuring end float by clamping the crank on one side an measuring down the side of the big end bearing. Mine has no discernible movement, but could that be because I( haven't stripped the sprocket end?

 

Cheers

 

[Pete Lewis]

has the looks of being run on poor oil at sometime in its life

 

the  dull light scored shell is not abnormal but the crank  has suffered , needs a light grind  if you are doing a decent rebuild its worth while 

 

Pete

[dougbgt6]

Doesn't look very bad, but you've got it opened up so you might as well get a re-grind and do a proper job. If you do that you'll be replacing the shells and the end float bearings come with the kit, (well they used to!)

 

My end float was so bad that I could get hold of the fan and push the crank back and forth almost 1/4 of an inch.