Spitfire Tappety Tappets??

[Banksy82]

Hello all - looking for some guidance/wisdom.

I have searched as best I can and I hope you can help from here?

I have recently bought a 1973 MKIV (late) Spitfire and I am going through the car just trying to tune and tidy up some outstanding issues.

I have what I believe to be excessive valve train noise. It is very 'tappety' to the point that the noise is clearly audible (almost loud) at 60 with the roof up.

I expected some valve train noise but I owned a similar but early MKIV 20 years ago and I don't remember it being as bad so I am leaning towards it not being 'normal'

I have done the usual tune - Plugs - points gap - timing and backyard carb tune.

I also checked the cam timing which is on the rock at about 1.5degrees after TDC (I believe this is within tolerance?)

I have checked valve clearances and found that the rocker faces and rocker shaft to be worn (the rockers only a little but the shaft quite considerably.) I replaced the shaft and dressed the rocker arms with a stone to remove the damage so that I could set the valve clearances correctly and reassembled - no change to the noise.

With the noise audible at idle I have been around the engine bay with a long screwdriver and a left ear and I cannot track it down.

To the naked ear it sounds like it is coming from the rocker cover but I know this can be deceiving. Changes as you would expect with engine speed (never goes away) and to me sounds like the frequency of valve train. 

Current suspicions are:

1) Cam / cam followers

2) I'm convinced it is nowhere near the front but possibly chain tensioner?

3) Something else entirely!

For further info I also definitely have throw-out bearing noise - whines like mad in neutral with the clutch out. but clutch position has no affect on tapping noise and seems nowhere near noise location. Clutch currently operates just fine so it is further down my list!

Any ideas gratefully received.

 

 

 

 

[RobPearce]

If there's wear on the rockers, it can often be impossible to set the tappet clearances correctly with a feeler gauge. If you dare, there's a trick whereby you run the engine with the rocker cover off and gently press a wooden dowel on each of the tappet adjusters in turn. If the noise reduces when you press one then that one needs pinching up a little.

[Banksy82]

Thanks Rob, I will try this this afternoon.  

I take it I float the dowel onto the push rod side of the rocker and not on the valve end?

I did dress out all of the wear on the rocker tips to allow me to set the clearances. I was careful but I could easily have changed the profile slightly so cannot guarantee that the clearances are perfect.

[Dannyb]

As above you can find out which tapes are making noise.  I found a Click Dial adjuster pretty good. 

You may have a cam follower noise also. 

Danny

[Banksy82]

 @Dannyb @RobPearce Tried the dowel against the adjusters trick. I let it ride on the adjustment screw and applied a small downwards pressure and couldn't discern any difference in the noise from any of the 8 rockers.

Is there any way short of removing the camshaft and tappets to determine if they are the source of the issue?

Next question is driving the car with suspected worn tappets going to end in catastrophe??

Thanks Again...

[standardthread]

Timing chain and gears with the noise resonating through the cam shaft? Especially if you had excessive wear in the rocker shaft.

[Banksy82]

@standardthreadI thought about this too. I have just been out and had a listen with a long screwdriver against the cover - all seems quiet. Same technique shows a definite rumble from the alternator bearings that is inaudible without so I think the technique is sound. I guess there is no way of knowing without pulling the crank pulley and cover?

The more I listen to it at idle the more normal it sounds, obviously it increases in volume with revs and I just can't think that I should be able to hear it at speed...

I can try and attach some audio but things never seem to come across that well in recordings...

Thanks for all of the ideas.

[standardthread]

17 hours ago, Banksy82 said:

Same technique shows a definite rumble from the alternator bearings

 

Simple test to find out.

Remove the fan belt and run the engine with the alternator running

[Banksy82]

@standardthreadThanks - tried removing the alternator from the system and no change. I was more suggesting that if I could hear bearing noise from the alternator with the screwdriver method and the timing cover is quiet then I can rule the timing chain and tensioner out? 

I really don't want to have to undo the crank nut if I can help it!

With the valve train sounding normal at idle and clattering at speed I am wondering if the two noises are actually the same? 

I might invest in a stethoscope to try and track this down.

 

 

[PeteStupps]

23 hours ago, Banksy82 said:

Is there any way short of removing the camshaft and tappets to determine if they are the source of the issue?

You might be able to see damage to a cam lobe from the bottom end, with oil drained and sump pan off. Good opportunity to properly check crank thrust and bearings if you're lying down there.

Pretty sure you can see most if not all the cam lobes - decent head-torch is handy. But can't promise it would be a conclusive exercise of course!

Before all that though, have you had a 2nd opinion or is there a friendly Spit / Herald owner in the neighbourhood with whom you could compare noises? Not casting doubt on your suspicions, just sometimes another pair of ears / eyes helps.

[Banksy82]

@PeteStuppsThanks for the input! That is worth knowing - I have quite the oil ring around the sump gasket so dropping this is on the list anyway. 

I'm doubtful of my suspicions myself and a second opinion / comparison would be really useful. I'm in Denbighshire, North Wales and yet to find any local Triumph owners - although I did spot a Stag today at Tesco!

If anyone knows of a friendly ear nearby I would be grateful.

[standardthread]

1 hour ago, Banksy82 said:

I have quite the oil ring around the sump gasket so dropping this is on the list anyway

 

Are you sure the oil is coming from the sump gasket and not the timing cover oil seal?

It's surprising how much noise a timing chain tensioner makes if it is worn, as was the tensioner in my last Dolomite (same engine). It had been replaced by someone in the past, badly.

If you were dropping sumps etc. by the time you have finished it would be easier and quicker to take the engine and box out and re-con the engine because it sounds like you have a worn engine, reason I say that is that I have never had to replace a rocker shafts in nearly half a century, even in engines that have gone round the clock. 

 

[Banksy82]

@standardthreadNo, not sure the oil is definitely from the sump gasket but the block is 'dry' above this line and it seems that someone in the past has attempted to silicone / rtv the sump to excess.

I do need a new release bearing and was in two minds as to pulling the box from the inside or just pulling the engine and box together out of the front.

I have compression values of 170, 160, 165, 170 (Engine warm but no oil down plugs), there is no knocking that I can hear and decided that the motor was basically sound.

What would be the usual overhaul parts / time for these motors? Would you change all bearings as a matter of course or inspect and reassemble with original parts if okay? I took my previous spitfire off the road for a bodywork resto and it took years. I would like to enjoy this one on the road and I don't particularly want to sink an enormous amount of cash into this but a winter project could be entertaining.

Thanks

[RobPearce]

I wouldn't worry about tappet noise. If you had bottom end noise or no oil pressure then a rebuild is in order, but if it's running well and has good compression, and the only problem is tappet noise, then don't panic. But as Pete says, you should find an experienced ear for a second opinion.

[standardthread]

13 hours ago, Banksy82 said:

I do need a new release bearing and was in two minds as to pulling the box from the inside or just pulling the engine and box together out of the front.

What would be the usual overhaul parts / time for these motors? Would you change all bearings as a matter of course or inspect and reassemble with original parts if okay? I took my previous spitfire off the road for a bodywork resto and it took years. I would like to enjoy this one on the road and I don't particularly want to sink an enormous amount of cash into this but a winter project could be entertaining.

Thanks

I took a week off work to do my first engine out and re-built by myself because I had asked a garage to do a clutch change, they did but didn't tell me the rear engine oil seal was ify. The clutch lasted a month, a new oil seal was 50p (time flies). They would pay for a new clutch (if defective) I would have to pay for labour (£30), 1974 prices. I did the re-built, rings, clutch, everything for about £40. The time included bus trips to get parts, in total, about four days.

In terms of cost now, it will depend on what is needed, or, if you want to go down the route of preventative maintenance, all bearings rings seals etc. When I did mine I had the massive advantage of local factors for rings and bearings and a dealership for seals etc.. Don't forget the recessed lip/gasket for the cylinder head!

With the engine and box out as one lump you have the additional advantage of checking the clutch and replacing if needed. And to get them out it is simply four bolts off the prop and two nuts each off the engine and gearbox  mounts.

If your car is a week-end drive having done all that you could have a car that is maintenance free for many years, mine are daily drivers.

Edited August 29, 2022 by standardthread

[PeteStupps]

20 hours ago, standardthread said:

If you were dropping sumps etc. by the time you have finished it would be easier and quicker to take the engine and box out and re-con

Can't agree with that! My experience is that's two afternoons versus severely months... not to mention the cost

(Edit: you're obviously a faster worker than me!)

Edited August 29, 2022 by PeteStupps

[standardthread]

It was needs must, I needed the car for work, minimum 300 miles per week just to get there.

[Banksy82]

Thanks all.

I think I will monitor the noise and wait until I drop the pan to fix (or at least improve) the leak and have a look at the general state of things down there while I am at it.

I believe the crank end float is worth checking - is there anything else worth looking at while I am in there?

[PeteStupps]

I would be inclined to take the centre main bearing and one or two big-end caps off and have a look at the bearings and crank pin/ journal surfaces. If you're not sure what you're looking for, post some photos of the bearing surfaces on here and hopefully you'll get some helpful advice! 

Strictly speaking you're supposed to renew big end bolts every time but I've been known to skimp on that for the sake of an inspection. You do want to torque them back up properly though.

If you do take the shells off, slide the bearing out of the shell and see if it's marked STD or -010 or whatever, so you'll know what size they are.

Apart from that, you can also peer up into the cylinder bores to see if there's any deep scoring. And of course, you can scrape the oil sludge out of the sump and see if there's any worrying shrapnel stuck in it... hopefully not!

Pete.

[RobPearce]

7 hours ago, Banksy82 said:

I believe the crank end float is worth checking - is there anything else worth looking at while I am in there?

You can check the end-float without getting "in there". All you need is a glamorous assistant to press the clutch, while you watch the front pulley. With the engine running it normally settles back to a neutral position, so pressing the clutch will move the pulley by about half the end-float. If you can see it move then it's a bit too much, but if you're not quite sure then it's probably OK.

[Banksy82]

Thank you for all of the input. Of course I can check the end float without opening up - I don't know why I was thinking otherwise - I'm an idiot!

 

[standardthread]

10 hours ago, RobPearce said:

You can check the end-float without getting "in there". All you need is a glamorous assistant to press the clutch, while you watch the front pulley. With the engine running it normally settles back to a neutral position, so pressing the clutch will move the pulley by about half the end-float. If you can see it move then it's a bit too much, but if you're not quite sure then it's probably OK.

You could probably get an idea of end float in numbers.

Taking the above one stage further run the engine, to centralise the crankshaft, stop the engine. Mark a spot on the timing cover as a reference point. Cut a piece of angle iron or similar to very nearly fit between the back of the crank pulley and the timing cover mark and file the ends of the angle square.

Apply the clutch to push the crank forward. With angle iron back in place measure the gap between the end of the angle and crank pulley with a feeler gauge. Or use an external micrometer if you have one.

To remove any eccentricity of the crank pulley in the measurement repeat, but before measuring the gap rotate the crank by hand 180’

If you drop the sump as well as a visible inspection of the bores touch gives an another impression of wear or scoring.   

 

[Banksy82]

1 hour ago, standardthread said:

..You could probably get an idea of end float in numbers.

 

I should be able to get a dial gauge on the pulley. and have an assistant depress the clutch. 

I believe the tolerance is 6 - 14 thou so assuming the crankshaft has centralised if I am reading 3-7 thou play I should be okay?

[drofgum]

Banksy,

You can also find the full end float by simply depressing the clutch pedal then with your dial indicator set up levering the pulley back towards the block.

Regards,

Paul

[Banksy82]

Bad news... crankshaft end float is in the order of 50thou!

I am beginning to think the noise could be bottom end after all - it is just more high pitched than any knocking I have heard before! 

With the clutch needing work also think it is probably engine and gearbox out time? What do you all think?

 

Cheers