Sprint engine - loud ticking

[red&black]

While the radiator is out it's worth checking which way round the long bolt through the alternator is fitted.
I put them in from the back so that the alternator can be removed without taking the radiator off in future. When built,the bolt was put in from the front.

James

[Mad Mart]

While the radiator is out it's worth checking which way round the long bolt through the alternator is fitted.
I put them in from the back so that the alternator can be removed without taking the radiator off in future. When built,the bolt was put in from the front.

James

Depends on whether you have a six or twelve vane impeller. One of them gets in the way of the bolt from the other side.

[GrahamFountain]

My memory of accessing the timing chain and jackshaft with both the head and sump cover on is that it's easy to get the chain cover off, but getting it back without damaging the front ends of the sump cover gasket or head gasket is not so easy. So I agree with the idea you should take the cam cover off first, and only take the chain cover off if that don't show the fault. You can run the engine with no cam cover if you keep fingers out the way and don't mind the bit of oil splatter. I've never run with the chain cover off. I suspect that may make more mess on the drive than wife would tolerate, but I could be wrong.

I run the herald with the lid off when setting the tappets - on the pushrod engine you can put a screwdriver on the rocker arms and damp their movment to see which tappets are noisy - you can adjust them with it running as well. But I've not looked to see if it's possible to get to the buckets on top of the Sprint's inlet valves to damp them that way and not sure if it would work either. Should be possible to find a noisy exhaust one though.

As an aside, I replace all the cam cover screws with Allen key cap screws whenever I have chance. I always seem to have problems with oil leaks from the bottom rear corner of the cover with Philips screws. I think they're 1/4" UNC from memory but I'm not certain of length. You can get 10 black high tensile 1" ones for under two quid off eBay.

As to the carbs: they are, as you say, SU HS 6s, as they should be. But I'm not sure I've seen the black plastic dashpot filler/damper caps like those ones, other than on SU HIFs. Not sure if it matters though.

Graham

[soe8m]

What do you expect to see running the engine with the cam cover off besides the same sight as one that found oil in the desert?

Jeroen

[GrahamFountain]

What's the problem? It's just diagnostics.

I know it's gonna be a bit messy, but it's not like all it's going to sheikh all the oil out straight away.
And if there's too much mess, just stop.

It might take a bit of care and a brave heart, to check the inlet valve buckets with the engine running. But I'd at least see if it was possible to give that a go before I went anywhere near taking the timing chain cover off with the head and sump cover still on, again. If the problem ain't at the top, then nowt much is lost.

An alternative, if it's too messy or scary even at idle, might be to pull the plugs and spin the engine on the starter - see if the noise is still loud enough to trace.

Graham

[Bradman]

What's the problem? It's just diagnostics.

I know it's gonna be a bit messy...

Hi Graham - I actually plan to do this, to visually check if the valves are sticking, and measure the valve clearances. I will get a helper and use the starter motor method I think, good call! Not looking forward to taking the spark plugs out to be honest - I took out 1 and it was very, very stiff (why do people tighten them like that??). I don’t fancy dealing with a snapped plug in this head, so plugs out will be last on my list :-O. My dad used to check the valves on his push rod powered Spitfire while it was running - I’m far too clumsy for that! Cheers! Mike.

[GTS290N]

Sprint cam cover hex head socket screws in stainless are available from the club.
There was a video on you-tube of a slant running with the cam cover off. Didn't run long! Messy!

[GrahamFountain]

I will get a helper and use the starter motor method I think, good call! Not looking forward to taking the spark plugs out to be honest - I took out 1 and it was very, very stiff (why do people tighten them like that??). I don’t fancy dealing with a snapped plug in this head, so plugs out will be last on my list :-O. My dad used to check the valves on his push rod powered Spitfire while it was running - I’m far too clumsy for that! Cheers! Mike.

You could add a wire from the battery around the ignition switch, but if you have a friend...

Don't know why they over tighten plugs. Used to cast iron heads I guess. I've not had one snap, but I picked up a head with no threads in one hole once. Had to have it helicoiled. No memory of what it cost. Someone who said he knew what he was talking about told me, for the Sprint, hand tight plus a 1/4 turn, though I've heard plus half and plus 2/3rds said as well. I stick with the plus 1/4 turn and never had one come loose.
There's at least one thread somewhere here on plug sockets - there are a number of issues with plug sockets for the Sprint, and it sounds like your lucky enough yours fits. I used to have two thin wall ones, one with a rubber insert for taking the plugs out and one without a rubber on a locking extension bar for putting them back. The one with the rubber left the rubber on the plug top if used to put them in, and the one without left the plug down the hole if used to take them out. Without the locking extension bar, sometimes the socket without the rubber stayed with the plug down the hole - a right proctalgia. I now have a very long, thin wall, magnetic, 3/8th drive one that cost me a tenner, IIRC, off eBay. That works an absolute treat, and I wouldn't dream of being without it anymore.

The OHV 1300 engine in my Herald that I do that with is actually 1/2 Spitfire - with the late MkIV big valve head on a Herald 13/60 block.

Graham

[soe8m]

Make sure you have a recorder running while trying. It will make a nice video.

Jeroen

[Bradman]

Sprint cam cover hex head socket screws in stainless are available from the club.
There was a video on you-tube of a slant running with the cam cover off. Didn't run long! Messy!

I’ll be getting some of those... mine are already chewed I’ve seen that video, very messy! I’ll be using lots of covers, for the drive and my wife’s blood pressure more than my bay

[Bradman]

There's at least one thread somewhere here on plug sockets - there are a number of issues with plug sockets for the Sprint...

Yes, I’m lucky - I’ve had an old Halfords socket set since the early 90s, it has a couple of plug spanners, one of which works a treat!

[Bradman]

Make sure you have a recorder running while trying. It will make a nice video.

Jeroen

I certainly will! Rubbish weather here right now, and as I’m a 1974 I’ll probably seize up in the rain even if the car doesn’t The next sunny weekend I get, I’ll be getting into this and will post what I find...

[Bradman]

A very quick update:

The loud ticking noise is gone!

https://youtu.be/M-lUrzP-GLU

(the small ticking noise is the electric fuel pump, that will soon be removed)

I’ve not yet followed the advice from previous posts - but only because I want to stock up on gaskets, socket head rocker cover screws and anything else that might break / get lost beforehand!!

What I did do was replace the mechanical fuel pump. I have a few spares, and the one on the engine didn’t work and was sealed by leaking black silica (I later found out that no gasket was used either, and the pump looked like it was from an OHV from the arm shape ). Apart from taking half an hour extra to clear away all the silica, a spare slant pump was on in no time, assisted by fortunate jackshaft lobe positioning

I started her up just to check the pump - and was amazed at how silent she ran. Could the noise have been a dead fuel pump? Don’t get me wrong, the engine still sounds like a diesel , and I’ll be following the above steps, just in case the pump swap is a red herring.