Mucky Head!

[fox889]

Adjusted valve clearances & disappointed to see black sludge laying fairly visible on top of the head (underneath the rocker cover obviously) you can run your finger over the head and pick up some sludge/grime or whatever! The previous owner had the car for 14 yrs but unclear how well he looked after her, I've done a couple of oil changes and the colour of oil goes off (blackish) after a thousand miles or so.

The rocker shaft looks grimy and a tad dry.

She runs fine, no smoke, nothing.

Question is, do you suggest removing the rocker gear and cleaning it or remove the head?

Where does the oil travel from the pump to the rocker shaft, is there an oil channel to clean out on the rocker shaft?

 

Thoughts much appreciated.

 

Nick.

[TriumphV8]

The oil travels from pump via gallery to main and cam bearings.

The rear cam bearing has a channel from bearing to hollow rocker shaft.

Normally nearly no oil would drop out there but there is a flat spot

on the cam itself. When the flat spot is in the proper position

it connects the incoming channel from the pump with the channel to the rocker shaft

and a little splash is allowed to pass each revolution.

 

Sludge in areas where there is no constant oil stream was quite normal

in older engines with the old oil of those days.

Today it is rare but one should be carefull to fill in modern oil that can pick up

sludge better and will transport it away and will get worse by doing that.

 

Frequent oil change seems to be a good solution

and although the colour is really black it is not that bad

for the engine because it is similar to carbon what lubes.

 

Removing the head is a question about DIY.

If only the head and manifold gasket must be bought

a decarbonisation is a good idea after 14 Years and

valves can be regrind and guides can be looked after.

If the job is done by a specialist that can cross the 500GBP easily

and than keeping all as it is might be a better choice.

[RogerH]

Hi Nick,

the black muck is usually carbon from combustion products blowing by the piston.

Can it be kept clean - not really as there is always some blow-by.

However you may have years of sludge in the sump. Why not drop the sump and give that a good clean.

 

How many miles do you do in a year and a typical drive out.?

 

Change the oil and filter more often - cheaper oil - this may help clean the oil ways.

 

Think twice about flushing the system through - this could cause other problems.

 

Roger

[astontr6]

Hi!

This suggests to me not many oil changes or cold running or both. I would remove the rocker cover again and then clean off as much as you can from the top of the head, after having

removed the rocker assembly. Have you changed the oil filter as well? If your car does not have a spin on filter fit one, this will increases the life of the bearings. Also I would use a flushing oil to flush the oil system through.

 

The oil to the rockers comes from one of the camshaft bearings. You will see the hole in the cyl. head when you remove the rocker assembly. With the rocker assembly removed check for

wear on the underneath of the shaft for each rocker. If worn badly with scoring etc. replace also check the rockers for flats where they rub across the valve stem tops.

 

Blackness of oil. (There is blackness and blackness )This is a bit difficult to diagnose from a distance, I assume your car is a PI, but here are some pointers.

Check: spark plugs for rich running number 5 & 6 will always show richness on a PI but if seen on 1 you have a problem, compression (180psi av.), manifold vacuum ( Need to know CP or

CR engine), how clean is the air filter? Sludge in the sump as well?.

 

Bruce.

[fox889]

The previous owner had her for 14 yrs but covered minimal miles, he was a TR register owner & I thought (wrongly) that he had looked after her.......he hadn't!

 

Roger: I probably cover 2k a year but those 2k are generally decent runs. Oil & filter (Millers classic 20/50) at the start of the season also had thoughts of changing the mains & big ends over winter but was put off by other people's comments about "opening a can of worms"' I wanted to drop the sump & clean that out along with the oil strainer, something I really ought to do. Oil pressure not wonderful when fully hot.

 

Bruce: spin on filter fitted last year, new oil & filter every March time. Really want to renew mains & big ends but frightened what I may find or what it may lead to!

 

Appreciate everyone's views.

 

Nick.

[RogerH]

Hi Nick,

if the engine appears to be OK or there abouts then don;t panic if you remove a big-end shell and find issues.

You can put it all back together and it will still be OK or there abouts.

 

If it was me I would drop the sump and remove all the big end shells and see what you find.

If they look iffy replace with new ones. Don't bother mic'ing the crank it could worry you.

You could drop a main bearing shell and see what is in there. Not sure how many you can change insitu but do what you can.

 

This will put it together no worse than before you started.

 

if you find horror stories then you can make a plan for next winter.

 

or you can leave alone and simply run the car.

 

Roger

[jerrytr5]

It's an old car, the oil will turn black - that's just normal. If it hasn't been run much then the sludge could just be condensate mixed with the oil.

I'd agree with Roger. If you're looking for something to do drop the sump, clean it out and check a couple of bearings, the thrust washers and the oil pump.

At the top end remove the rocker shaft and check for wear (they do wear quite quickly).

None of these jobs will take that long or cost much.

Run it with a cheap oil to flush (I'd avoid 'Flushing oil' personally) then change the filter and put in something decent.

Then drive the nuts off it.

Jerry

[Blue cedar]

Nick

 

This autumn I dropped the sump and cleaned, concerned with the oil blackness. Concerned had not previously been looked after properly by po.Whilst there I replaced the big, main bearings and thrust washers. The original bearings were showing signs of wear. What a difference. Really quietened the bottom end. Then rebuilt the rocker assembly....new shaft and ground the rockers because of wear. Again, like the bottom end, the top end is now really quiet. The engine now ticks over really quietly and smooth. When drive through the revs the engine has lost that 'thrashy ' sound and is really smooth.

 

Be very very, particular when dismantling as it is easy to put parts back in the wrong order. Then you have got problems.

 

Cheers Peter

[fox889]

Strange thing is, she's been booked in at my mates garage 2 or 3 times themes this year but always backed out of doing the bottom end because of comments from said friend and others (some on here) mainly worried what can be found. Even have the sump gasket here since June!

 

Roger: I think this is the plan for feb/March time thanks, would you bother using plasti-gauge on the shells/ends or just replace?

I've read up (again & again) how to do this and it doesn't faze me (yet) so will have a go early next year.

 

Petr: Think I'll do the same as you & look at the shaft & also try and clean up the head without disturbing too much gunge! Never liked 'flushing oil' so will just keep changing the oil on a regular basis.

 

Thanks to all as per usual.

[RogerH]

If you are considering 'plastigage' then also consider mic'ing the crank journals. The TRouble is the more you look the more you will find.

 

Either remove the engine and do the lot properly or do a few little things that will keep the engine going for a bit longer until you are ready for the big one.

 

From your first post you appeared reluctant to do too much at present.

 

Roger

[Blue cedar]

Nick

 

I can not see why there should be concerns about what is found. You have confirmed the engine is fine, bar the sludge. If you take one bearing cap off, examine the lower bearing shell. Put back, torque up and move to the next.......and so on , what can go wrong. If you find some wear on a bearing you can stop, decision made for you and order a full replacement set. Same for the shaft. Cheers Peter

[fox889]

Roger: I'm only reluctant because of what 'others' say, I take notice of those who know more than me. I read an article that mentioned plasti-gauge so just thought I would mention it.

 

Peter: I think you're right, I just need to get on with it and see what appears! The engine is not 100% as she's low (ish) on oil pressure when hot and will also knock for a second or two on a cold start up if she catches straightaway, 5 secs cranking gets oil pressure before she catches.

 

Thanks again, advice much appreciated.

 

Nick.

[RogerH]

Your low oil pressure and slight knocking could be big-end/main bearing wear.

Drop the sump and check the bearings - you know you want to.

 

Roger

[Guest ntc]

Nick

Run the car as long as you need to,but things will only get worse you will never clean the oil ways without a full rebuild.

[fox889]

Roger: I do.....I do!!!!!!!!

 

Neil: Agree, will just continue to have regular oil changes and cleaning/dropping sump may also help!

 

Thanks chaps.

[Blue cedar]

Nick

 

Agree with the oil related comments above. My fresh oil has gone black quite quickly, unlike a modern day car. I cleaned a lot of muck after removing the rocker cover and dropping the sum. So will change the oil frequently to help matters.

 

I am not an expert, but I'd want to replace the bearings to try and get rid of any knocking. The Haynes manual recommends this course of action !!!!

 

Cheers Peter

[jerrytr5]

You're all getting a bit too precious if I might say so.

It's an old car. It will have black oil. It will mildly knock on startup. It will happily run for thousands of miles like that.

If you want modern engineering - I think you know what to do

Jerry

[Alec Pringle]

One of the early Goodwood sprints, a couple of young bikers had bought an absolute dog of a TR6 between them, determined to compete.

 

The late Dave Wilson and I gave them a hand, swopped the non-functional shockers for the old tired set I'd previously replaced on my car, and swopped the bald tyres for a discarded set of XAS which were at least (just about) legal. Bottle of dry cleaning fluid in the fuel tank helped clear the system, as did a packet of caustic soda in the radiator. The engine knocked like a Perkins diesel and a gallon of oil lasted considerably less than a thousand miles. Two changes of flushing oil and new filters later, a refill with Duckhams, tweaked pressure relief valve, and it wasn't quite as bad. But it still knocked like a bar steward on a bar maid.

 

The youngsters won their class regardless, tacho needle stuck firmly at the far end, and three or four years later the old dog was still rattling on.

 

As Jerry says, you can get too precious . . . . .

 

Cheers

 

Alec

[peejay4A]

I'm compelled to ask Jerry and Alec. Do your cars knock on startup and have black oil?

[TriumphV8]

One of the benefits of our old British cars is that they still run

although they are close to be dead.

 

But that does not mean that they do not benefit from modern tolerances

in bearings and piston to liner tolerances.

 

Be aware that good TR6 cam, main and big end bearings have a clearance of only 0.03mm

my pistons have clearance of 0.04mm, that is all like modern engines have.

 

Only some parts like the crank look a bit rustic

but that is no justification to keep such an engine in a more

or less worn state that it received during the last 40 years.

Edited December 23, 2014 by TriumphV8

[jerrytr5]

I'm compelled to ask Jerry and Alec. Do your cars knock on startup and have black oil?

The TR doesn't knock but the engine was rebuilt fairly recently (<20k). The oil does have a rich patina.

The 1300 Spit powered Hurricane rattles on startup and that was rebuilt even more recently. Lovely black gold. Both use Silkolene.

The Mazda 1600 powered Hurricane doesn't rattle and has translucent golden oil and it's done over 120,000 miles. But that's modern engineering for you.

Jerry

[poolboy]

I believe I'd check the crankshaft endfloat though or at least be aware of the symptoms of one laying in the sump.

[Alec Pringle]

Hi Pete,

 

you wouldn't call the V8s quiet on start-up or the oil golden, but they ain't broke yet . . . . .

 

When they are we'll fix 'em !

 

Cheers

 

Alec