K series cambelt change - in situ?

[murph7355]

And so the numpty questions begin in earnest.

Can a K-series cambelt be changed in situ?

Have watched a couple of vids on how it's done but all have the engine out.

Assuming it can be done in situ, I'm assuming I get the timing marks aligned, put in a cam locking tool and change the belt?

Should I change the tensioner too?

[garybee]

Yep, loads of room.  Do you have an apollo tank?  Only ask as one of the hoses will need removing if so.

I would suggest marking the pulleys and old belt with tippex then transferring the marks to your new belt.  Can't get it wrong that way.

I wouldn't bother changing the tensioner if I was only doing it on age, not mileage.   

 

edit: What spec is the engine?  Is it EU2 or EU3, VVC or fixed timing, wet sump or dry etc?

[Wrightpayne]

If manual tensioner you can use the slightly wider VVC belt - part number is in the archives.

I've changed mine several times and always done the water pump (ensure it has metal impellors and a vent chamber) and the manual tensioner bearing. That said I'll take Gary's advice on the bearing next time!

Front crank pulley needs to come off - I wedge a big flat screwdriver against the ring gear. Dont be tempted to use the timing triggers on the flywheel! 
 

If it has verniers fitted the cams will need retiming. If its a VVC there is an extra rear belt to fit.

I found the Haynes manual for an appropriate Rover useful for engine stuff - procedures, torque settings etc.

Regards

Ian

[SM25T]

Belt, tensioner, water pump. Spots of Tippex on pulleys (2 places on each toothed pulley) and accurately on belt edge. Transfer dots to new belt.

[Bricol]

If you don't touch the cam pulley bolts, verniers or not, it won't need re-timing - they will stay correct to the cams.

Set the engine to whatever position the manual says (DVA site suggests 90 DBTC if I remember), mark the pulleys so you know where they ought to be and away you go - you don't NEED a locking tool (I don't have one) but I guess its easier.

I've seen a method of making you feel better mentioned with other engines, but I don't know if there's enough room on a k-series, I suspect not on the bottom pulley - push the existing belt back as far as possible - slide the new belt on . . cut the old belt off.

I undid the crank bolt in the car with it in gear, handbrake on and someone pressing the brake pedal - nothing broke, nothing twisted :)  Now I'd use a big air impact gun :) - although a guy in the USA used an even bigger one on a Lancia integrale enginer - commented that it had seized when he posted a piccie of his bust crank - the impact gun had sheared the end of the crank . . . thats when I mentioned it was a left hand thread . . . he hadn't checked or asked  . . . I can't remember if the K-series one is or not . . .

[Wrightpayne]

There is about 7 degrees of movement on the bottom belt sprocket, which is free to move once the pulley bolt is undone. If it has verniers it will need the cams re-timing.

[SM25T]

K-series crank pulley bolt is not a left hand thread.

[murph7355]

Thanks all.  Good news it can be done in situ.

I was hoping to be abe to avoid re-timing...but it has Verniers :(

If each of the pullies is marked up fully, along with the belt, wouldn't that make it straightforward (with a bit of care) to ensure everything stays aligned?

Spec

• 1800K Accralite forged pistons (11.1:1 cr)  
• QED steel banded liners
• Std. rods and crank
• Lightened flywheel
• Piper 740 cams
• Piper Vernier pulleys
• Fully ported head with 31.5mm inlet and 29mm exhaust Paul Ivey valves (could be the other way round!)
• Solid followers
• Mike Satur uprated head gasket
• Jenvey DTH throttle bodies with 40mm trumpets, Pipercross sock filters and throttle linkage
• VHPD injectors
• Uprated fuel pump and regulator
• Emerald ECU
• AP Racing clutch
• 4-2-1 SLR non-cat race exhaust
• Mocal oil/water heat exchanger
• Race aluminium radiator
• Pace dry sump kit

Gives ~200bhp and very smooth delivery.

Will have a search for timing dials, but suspect that bit will be well beyond me...

[murph7355]

btw, car has probably done 40k-50k miles on that spec (plenty of track use) and been that spec for around 22yrs.  Don't know if the tensioner has been changed in that time (have the servicing paperwork so can check).

Also, crank pulley bolt - what torque is needed to do it up properly?  

[garybee]

Bricol and Wrightpayne are both right in that there are times when you do and don't need to time the cams after removing the crank pulley. 

With that spec of engine it will likely have been assembled with enough care that the slop in a standard crank pulley/key is enough to throw your timing out.  Some builders however will shim the pulley keyway so that there is no movement.  If that has been done then you do not need to time the cams so long as you reassemble the pulley/shim/keyway the same as it came apart.

So the answer for your engine specifically is that it depends what you find when you undo/remove the crank pulley.

Did that make sense?

[7 wonders of the world]

I'd would be clocking the cams before removing the old belt to see what ball park the builder timed them at.

 

[Geoff Brown]

Having owned a K series there are other components that require changing at the same time as the timing belt but I have seen a cheeky short cut to changing a belt. Not possible with a K series as from memory to remove the lower cover the crank pulley has to come off.

Cut the belt lengthwise down the centre with a Stanley knife then pull off the forward half. Fit the new belt then cut off the remaining half of the old belt.

A procedure only for the very brave.

 

 

[garybee]

You can still do that on a K.  You cut it in half with the engine running and top cover removed.  Still needs the crank pulley removing though so no use to the OP as he doesn't know if the keyway has been shimmed.  I've done it that way on cars when I'm changing the belt due to age but know the tensioners/anything else on the belt you might want to change haven't been on for many miles.  Got to be careful to keep your Stanley knife held straight though.

[MADMALC]

Hi M,
I used one of these   https://www.eurocarparts.com/p/laser-camshaft-locking-tool-rover-k16-LAS2626  Cheap enough and every little bit of help for a first timer is good. I used the 'white dot' and the 'in gear with the foot brake applied' tricks as well. Take your time plus check and recheck using photographs as a start reference.

[murph7355]

Thanks guys.

I suspect the safest answer would be to re-time regardless.  Which fills me with a degree of dread :D  Not least of which because the guys who did the engine work (and later the chaps at Emerald) did such a brilliant job of it that I don't want to mess that up, and I believe cam timing is key.

Still, what could possibly go wrong!  (I'm seeing this particular job as my biggest headache).

If I get chance this weekend I'll start to take it apart and will take photos. (Though think the in theory easier task of sorting my wheels/rear ARB drop links will likely come first).

[Wrightpayne]

You could always do what I did - fit the belt and let someone else time it in! I was advise to retard one cam and advance the other 10 degrees for a safety margin. 

DVA power has a write up how to do it and how to make the dial gauge brackets. 
 

Ian

 

[Bricol]

I must have been lucky - I never noticed any slop at all in the crank/pulley fit.

I hope I would of if there was -day job is designing, building, testing, improving and fault-finding where accuracy of fit is rather important!

I'll certainly wear my specs next time!

Is that the purpose of the cam locking tool - get it nicely in place, lock the flywheel firmly in place so that when you fit the new belt, it locates the bottom pulley as that's the (slightly) free part?

 

[garybee]

Bricol - Yours may not have any depending on what's been done.  You could have a crank and pulley that have been accurately keywayed during a (non Rover) engine build.  

The cam locking tool doesn't solve this issue for you I'm afraid.  I have a K-series in the row of engines that are in my garage at the moment.  I'll make a quick video tomorrow to show how much movement there is.

[Geoff Brown]

I changed my 1.6 K belt + accessories three times during ownership. It is straight forward.

Set TDC, use the ally locking block for the pulleys. Broad blade screwdriver firmly inserted in ring gear through off side hole. The rest as required.

Works every time with no problem. Honest!
 

[garybee]

You don't time the K-series with No. 1 at TDC.  The timing marks are set for 90 Deg before TDC.  Also as above, if you use this method for assembly with an unmodified crank/pulley your cam timing is not accurate.  

Edit: Actually this looks to have gone round once so will leave you to follow whichever advice you prefer OP.  Best of luck and hope it's all fine after being laid up 

[revilla]

Illustration of the typical (unshimmed) K Series crank pulley play issue:

[StevehS3]

Great thread and contributions. I have never changed a cam belt but for me part of owning a 7 is to learn such things. I was hoping someone local might show me but I think I will have a good read of the Haynes manual and do it alone over winter.

[Wrightpayne]

Without verniers to reset its quite straight forward.

I remember reading that mechanics, on certain cars cut the belt down the middle with a stanley knife - engine running :-0 Then cut one half off, slip the new belt on (the half left on keeping everything aligned) then once the new belt half on, cut the remaining old belt off and press the new belt fully home Jobs a goodun!

[StevehS3]

Job's a good 'en unless you slice through it completely - then job's a bad 'en!

Standard cams and no verniers on mine.

[murph7355]

Is that amount of movement enough to get the belt a tooth out?  It doesn't look to be.

Fanastic contributions so thanks everyone.  Keep it coming :)

First job will be to take the covers off an see what I have. 

I'm not fully understanding why Verniers add to the issues, assuming they're all tight.  More reading/video searching to do.

(And if it all looks like it's getting too much I'll get a pro' to check my handy work!).