240 head removal

[SKiddell]

Alan/Steve, the engine is out of the car.
I was in the short term just going to put a new head gasket and water pump on but what is the point of asking for opinions on here then ignoring them....
So a full strip down it is then....Gulp!
I will no doubt be pestering you all when it comes to re-build and new parts upgrades.
Thanks
Craig

Personally I think its a wise move Craig, the additional cost is not huge,

Hot tank £50
Rings, £150
Hone £100
Mains £70
Big ends £75
Gasket sets from £70 - £200 depending on whos make.
New water pump £30 - £50

You can buy cheaper or more expensive, this is just a guideline

Its a very straight forward job as long as you follow the basic rules of cleanliness and measure twice cut once.
The engine will live longer, feel and run better, and as long as you get it right there is no down side.

The major benefit is you can drive it around knowing that you did the work and learned something in the process.

Good luck, its rewarding and I find quiet therapeutic

If you need any help PM or ring me.

 

[Throttleton]

Thanks Steve.
I have mentally changed my view on the engine work from something which has to be done to something which may be fun..........I'll let you know if the latter works out true or not!!

 

[moonraker_tom]

Just to add; when I took my head off about 2 years ago, I replaced the studs.
Having once reused 20year old studs and sheared one (not under full torques) I would recommend spending a few £'s on new studs.

 

[Ian Patmore]

Further on from what Steve says, if you have not seen one, they fit in front of the head, with a couple of wheels/cogs which can slide against the timing chain, taking up the slack.

 

[Throttleton]

Yeah new head/manifolds bolts for sure.
I assume the Kameari sprocket is an easy adjustable affair for playing with different cam set ups??
If I want to keep the original cam is it needed other than the fact that the tensioner wont 'spring' out??

 

[Throttleton]

Got the head off. Decided to leave the manifolds on as the bolts were natsy.
That seems to be the right way as they are easier to get at when the head is upside down.
Duncan was spot on about the gasket. I don't think it would have survived a test start up never mind a blast round a track, so replace head gasket is a must if old/ /decayed.
The head bolts were totaly different with regard to torque settings. Some were able to be loosened with a standard ratchet/socket, some we had a 3ft power bar on to shift.
The tight ones I think we were very lucky not to snap but we spent a good while on them.
The 1st few movements on the tight ones were ars* nipping, with the power bar bending we heard a crack and thought the worst. In fact we thought the bar/joint had failed.
Whilst one of us was watching the bolt and one yanking as hard as he could (blimey)
we noticed the bolt moving. It took a full 4 or five goes to do one revolution and every time this 'crack' noise.
Anyways the head is off with no major problems. The piston tops are slightly covered in carbonised ****. Some appear much cleaner than others?? Is that a plug fault??)
The head and valves are much like the piston tops, some grubbier than others?? will need overhauling but all in all so far so good.

 

[rallymanDP]

And as Alan and others have already said, the Piston Rings and the internal Bores will be gummed-up with years of Carbon and that Varnish that acculumulates with storage and will still make the Engine smoke when started again, so -

Do the decent thing, and STRIP THE WHOLE THING DOWN !

You will be much happier with the end result, and at the very least, you won't have anybody on here saying " I told you so"......

 

[Throttleton]

I'm on it Duncan, total stripdown.... You will be sick of me pestering you though

 

[MaximG]

I reuilt my 240 engine a year and a half ago and enjoyed it e
imencly. I am now in the process of rebuilding a 2.8, challenging but very fullfilling. By the way I intend to fit the Kameari sprocket set if only because I love the sound it makes.

Mike B

 

[Throttleton]

Mike I hope I enjoy the rebuild as much as you!!
You are the 2nd person to comment on the sound of the Kameari sprocket.....
Other than the sound why are you doing it. Are you adding upgraded cams???
I don't give a dogs c*ck about the sound, I just want to build a stock motor as good as can do it for now.
Anyway the sound will be drowned out by my custom side pipes!!

Ok Frenchy time for you to pipe in (get it) and call me a *****er.

 

[Rob Gaskin]

Few inputs:

Manifold Studs - yes renew, well worth it.

I wouldn't have turned the carbs upside down, it just doesn't seem right to get any **** spread around inside them.

Those standard exhaust manifolds are **** but they sure seal better than a 6 branch.

The big waterway opening at the rear of the head can corrode into an even bigger one, I had to have mine 'built-up' when my engine was rebuilt.

It's all a bit black and oily so yes check piston rings and valve guides/oil seals.

Sprocket - my standard sprocket works just fine.

If you replace everything that's worn you'll replace everything so get advice from a tight **** (Duncan might help ). Don't treat it as a race engine, just a basic Datsun engine that needs to run reliably and have reasonable compression.

Good luck.

 

[rallymanDP]

Well, Thanks for the Character Assassination there, Rob ! Well, all true, I suppose....

Just a word on the expected costs, Craig - Skiddy is bang on with the cost of rebuild parts, etc., but in case you get carried away, the Kameari Timing Gear Conversion will cost you at least as much as the rest put together - around the £750 area, and moving all the time with the exchange rate.

Bring the Pistons down to our place sometime & I will show you how to recon them to virtually as good as new condition, and why they are so important to do.

 

[Throttleton]

Good points Rob,
I was planning on taking the carbs home and cleaning them with the utmost care!!
The manifold thing...Mine has a bit broken off the end where the last stud is, so I thought I might as well get a stainless affair.
750 quid..... no one has explained why I need 1 on a standard cam

 

[Rob Gaskin]

The manifold thing...Mine has a bit broken off the end where the last stud is, so I thought I might as well get a stainless affair.

Buy the essentials first and see how much you have left out of your budget - I bet I can guess .

We need to see this car finished and running - not half finished but with some nice bits.

I'm going to stop now, honest

 

[MaximG]

- not half finished but with some nice bits.

I have come to the conclusion a Z is never finished.

The only reason I started on another engine was because I was bored not having something to play with. I keep having to remind myself that with this engine there is no hurry and that I can take my time. The cam is a fast road / rally cam at least that is the spec given by Kent Cams. Its John Palmer's old engine that he replaced, unfortunately it sustained Valve and Guide damage just before he took it out which has unfortunately boosted the rebuild cost. I new it had some damage before purchase but I don't think John even realised just how much. I have a whole rake of things I would like to upgrade before the engine goes in such as electric fuel pump, electric fan, 280 alternator plus I have started to put together body panels in lieu of sorting out the body work. As I say these cars are never finished.

Any way onwards an upwards.

 

[zbloke]

750 quid..... no one has explained why I need 1 on a standard cam

On a standard cam you don't need one, put the money to better use on your build

 

[Throttleton]

Thanks zbloke glad about that.
I'll have a look at the waterway today Rob and take a pic.
The cam side off the head was all still covered in oil and looks healthy to the eye, but the valves are covered in crud on the other side. Wasn't to keen on taking the cam out, will I need to to clean up effectively??
I think I could clean up pretty well but wondered about the valve seats?

 

[SKiddell]

The Kameari dual sprocket set up will not give you much of a benefit on a standard engine (other than increased stability of the valve train and not having to worry about the tensioner pop out) but how long does an engine remain standard ???

Going back to my earlier post, I would highly recommend the little brother of the Kameari dual sprocket system
Its an uprated version of the OEM unit with a sliding bar which prevents the tensioner poping out....thats worth having.

Sprocket - my standard sprocket works just fine.

If your running a performance cam, an adjustable sprocket give you the best oppourtunity to get the valve timing bang on, for large lift/large overlap cams an adjustable sprocket is almost mandatory.

I wouldnt discount anything until you have a full and complete understanding of where you want to get to with the engine and car, not just today or tomorrow but in 12 months or several years time, investment today could save reworks later on.

If all you want is a reliable daily driver that will never make more than 150HP then a nice, well thought out and executed rebuild will suffice.

But any performance modifications have to be well thought out and planned.

 

[Albrecht]

I think somebody needs to convince Throttleton to actually take his engine apart completely and properly, rather than distract him with any talk of 'upgrades' or even mildly fancy tuning parts.

Am I dreaming this, or is he actually trying to avoid removing the camshaft from the head ( and therefore avoiding removal of the valves themselves )?

The cam side off the head was all still covered in oil and looks healthy to the eye, but the valves are covered in crud on the other side. Wasn't to keen on taking the cam out, will I need to to clean up effectively??
I think I could clean up pretty well but wondered about the valve seats?

I've dealt with fibreglass and composites people several times in the past ( or tried to), and every simple one of them has been barking mad. I reckon it's the fumes, you know......

 

[Rob Gaskin]

If your running a performance cam, an adjustable sprocket give you the best oppourtunity to get the valve timing bang on, for large lift/large overlap cams an adjustable sprocket is almost mandatory.

I wouldnt discount anything until you have a full and complete understanding of where you want to get to with the engine and car

Steve, I do honestly understand * what you are saying but you always go down the expensive route and I don't think Craig wants this. I'm prepared to accept compromise because I don't want to spend a fortune on my hobby, it costs enough as it is. If I was competing perhaps things would be different. I don't think Craig is too concerned about ultimate performance at the moment and if you prepare for possible future development where do you stop?

There is very little on my car that you would be happy with but I THINK Craig is more after my sort of engine than yours to get his car mobile.

*When I built an Imp engine many moons ago I did 'time' the cam using a special sprocket and dial gauge (the head and block had been skimmed a fair bit so valve timing was 'out').