MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

TR parts and Triumph parts, TR bits, Triumph Car Spares and accessories are available for TR2, TR3, TR3A, TR4, TR4A, TR5, TR6, TR7, TR8, Spitfire and Stag and other TR models are available from British car spares and parts company LBCarCo.

Triumph TR6 - Bad Day

Well another TR6 adventure
Wife and I were driving today about 100 km (60 miles from home) when I started slowing down to a stop sign I hear this tappet sound. Pull over. Listen to engine- - open up oil fill cap and see broken valve spring. Pull off rocker cover at side of road and sure enough - piston 4 (intake I think)

Call U haul- book car trailer 30 miles away. Call son- come pick me up. Drive to one of my employees place (30 miles away but not too far from where trailer is) to use his company truck. Go get trailer, load up car. Deposit it in garage 2 hours ago (8 PM eastern). Go get a beer.

I hope there is no piston damage.

Any recommendations? I hope I can just replace the one spring without having to pull the head off.

Thanks.
Michael Petryschuk

Pends on what caused the springy to explode
DON KELLY

Mike
This is bad news. Maybe you are lucky and just the spring. Gotta agree with Don though...what caused it? Age like us guys?

Try this. FIRST: pull the plugs and turn engine over by the fan blade. Anything sound or feel wrong??

SECOND: Disconnect the coil and turn engine over a few times.

Make sure the valve can not fall down into the cylinder. Obviously inspect the other springs.

Good luck Mike.


Rick


PS maybe this is an omen to get your other TR on the road?
Rick Crawford

Don et al.

Any speculation on what may have caused it to fail?

The area is well oiled and even so oil will have no effect on reducing spring fatigue.

Excessive heat will decrease the life of a spring but I don't think that area sees excessive heat. Temp gauge runs well below H all the time (1/3 scale max. But that is not to say that in its previous life 1969-1982 it didn't see hotter temperatures. Or the fact it sat unused and in pieces for 20 years where the springs were unoiled and the head sat loose on the block.)

I believe the choices are spring fatigue which may suggest the other springs may go soon, a defective spring which suggests that all I have to do is replace this spring, a miss aligned spring putting stresses on the spring in the wrong spot or corrosion of the spring due to sitting unoiled for 20 years which suggests the other springs may be at risk. Anything else you can suggest?

When I pull it out, I will post a picture and comment on the valve movement and valve guide. (all guides were within tolerance when I did the engine in 2004.
Michael Petryschuk

Rick I see you were posting as I was composing.

See attached- clean break at spring.
It is the piston 4 exhaust valve- not intake as previously mentioned.



Michael Petryschuk

No excessive valve guide play- seems good and tight. Valve moves freely up and down.

Can't see how it could me misaligned- the keepers were secure(and actually held together which was good)and the other components appear in good shape.
Michael Petryschuk

I guess one last comment at this time-

Engine had about 50000-55000 miles on it when it was taken off the road (not exactly sure since speedo was changed somewhere along the way- 35000 on old speedo, 18000 on replacement speedo but not sure if it started at 0 when it was installed and there were several long periods of time where car was run with no working speedo)

Rebuilt engine has 13000 miles on it.
Michael Petryschuk

That sucks. If your valve didn't fall into the cylinder, you might well be OK. I don't see how it cold be put together missaligned. If you have compressed air, make an adapter out of on old apark plug. Put the cyl your're working at TDC screw in the adapter, plug in the air and the air pressure will keep the valves from falling into the combustion chamber while you change the springs. I'd do the whole set just for piece of mind.

Rob
rw loftus

Michael-The "rope trick" works very well for holding the valve in place. Remove rocker arm assembly, put piston near bdc, stuff as much clean rope into the cyl. and turn crank gently to bring piston as close as possible to the top. I have had one valve spring break, replaced it, and never had a repeat performance. Sometimes, it is just a random thing.
Stuff rags into all openings in the head before removing the valve keepers or they could end up in the pan or worse.
Berry
BTP Price

Shoulda had one of them there oil feed line thingy's to keep things well lubed up there at that top end....OK, I'll stop.....
JT White

Are these stock springs or "uprated"? The reason I ask is it's easy to install uprated springs wrong. For instance with the compression spacer when it's not needed.
Brent B

Rob and Berry- Thanks for the ideas. Both are great methods and now I have more confidence I won't have to pull the head off.

It is somewhat reassuring that Berry had one fail, replaced it only and hasn't had a repeat. So now the tough decision- to do all or one.

As far as I can tell the valve spring even though broken prevented the valve from hitting the piston.

Brent- Valve springs are stock and the originals.

Thanks for the quick jab and advice JT but I don't believe this failure to be lube related. :-)

Michael Petryschuk

I don't either ; ) Good luck with it.
JT White

Interesting thru all this discussion . A push rod has not been discussed.
My first thought
DON KELLY

Don-How would a push rod cause a broken valve spring?
Berry
BTP Price

I know you don't want to hear this, but I think you should replace the valve. We don't know what happened to that valve when your spring broke. That valve may have some hairline cracks. If that valve breaks at highway speeds, you could have catastophic results that will cost $$$$.
benji

Gee Benji

Aren't you a harbinger of good news. But thanks for the advice.

Ordered a full set of springs today. Should have by Thursday.
Michael Petryschuk

So you will be at Bronte on Sunday?


Rick
Rick Crawford

I am playing it by ear Rick.

I have some family matters to attend to as well and am not sure I will have the time to install valve springs, wash car to make it show presentable (is covered in bugs and dust from the recent trips it has been on) , attend Bronte and deal with Family matters. Decision will be made Saturday so keep an eye for an e-mail from me and I will join you down if I go.
Michael Petryschuk

I have my springs. I tried half heartily to put one on tonight but really need the right tool or a second set of trusting hands to push the spring down while I afix the keepers

Does anyone know of a tool that compresses the valve spring so I can put the keepers on while the head is still on the block and still be able to release the spring?

The valve spring compressors I am familiar with work when the head is off.

Regards
Mike
Michael Petryschuk

Stuff rope into the cylinder, turn crank to raise piston and it holds the valve up.
DON KELLY

Place a ring spanner on the valve collar and compress the valve spring by pushing down on the spanner; get an assistant to drop the cotters between the collar and the valve stem.

Colin
C J Norcott

My post:

Cam/crank set to TDC firing on each hole you need to do this with, too.
DON KELLY

q'est que c'est this ring spanner
DON KELLY

Michael Petryschuk asks:

"Does anyone know of a tool that compresses the valve spring so I can put the keepers on while the head is still on the block and still be able to release the spring?"

Your answer is found in the 2010 K-D Tool Catalog, items #2078 on page 27 or #3271-76 (measure to make sure, otherwise go with the -75 which is 5/16" longer) on page 28. You can either use the rope trick or you can get their 901 adapator kit and hold things up using compressed air (you want a compressor with a big tank or that at the very least if it cycles on and off a bunch, one that won't throw the breaker).

Sorry, just noticed the image shows "902" in error, it should show 901.

SteveP1

Nother idea.

remove the rocker arms. bring the piston of the cylnder you are working on up to TDC. Piston will hold the valve in place enough to remove spring. No need for rope and a chance of bending something.
DON KELLY

Would it not be easier to buy a new head gasket and manifold gasket, remove the head and inspect the offending valve and piston for damage. This will allow you to use a typical valve spring compressor. As you are replacing all the valve springs you may as well take the opportunity to grind the valves. You should be able to do this in 1 day.

Colin
C J Norcott

Thanks.

Don- Ring Spanner= box end wrench

I had engine at TDC and air pressure to hold valve. My difficulty was pressing valve spring down, holding it while putting in the keepers.

Thanks for the tool reference Steve and ring spanner suggestion Colin.

Colin- I guess it depends on what is defined as easier. To remove the head etc will certainly be more time consuming and add additional expenses but make valve spring replacement more straight forward. And it does give me the opportunity to do a full visual inspection. The valves were ground 12000 miles ago so there would be minimal advantage to doing it again now. A full day of time is a luxury I don't seem to have right now. Probably the right thing to do is the full head removal but I sure want to do the fast thing so I can get in a little more driving time before the end of our season (which may mean 2 or 3 more drives of 200-300 miles each) and this may be clouding my judgment. I hate these types of decisions.

So I want to put this one spring on with the head on. Test the engine compression and performance and then go from there. If engine performs well then full head removal will be the winter project- if it doesn't full head removal immediately. Stay tuned.
Michael Petryschuk

Replaced all 12 valve springs today. My wife put the keepers in while I manually compressed the spring with a ring spanner. My palms hurt from pressing down on the wrench. Compression test and cylinder leakage test all OK. Car running well. No funny noises.

I guess we are back in business.
Michael Petryschuk

Good to hear....another success story (and the Mrs involved too....BONUS!)
JT White

I am pleased the ring spanner worked. Did I omit that it is tough on the hands. For Don, see the image of a ring spanner.

Colin

C J Norcott

We call that a "wrench" here on this side of the "big" pond....you say tomato I say tomatoe.... : )
JT White

Closed end box wrench
DON KELLY

This is what we call a box spanner

C J Norcott

That's a cheap wrench you get when you buy a mower or chainsaw :)
DON KELLY

Tough on the hands is an understatement Colin.

But I know how I would design a tool that would be a little easier on the hands.

I tried a tool from Canadian Tire first though.But it seems to be designed for American cars as it wouldn't compress the spring enough (spring too small or tool too large) and then it came apart in pieces. Don't buy the tool it is junk. (the trade name is Power Built)

I will mention as well I had about 30 psi air on the cylinder while doing the job to prevent the valve from falling into the cylinder.

Michael Petryschuk

Just to close out this thread. Put a 100 miles on the car today. All seems OK. Ran as well as before. Whew- big sigh of relief.

Only problem was the weather- 16 celcius / 60 F, sporadic light rain, over cast. Ran with the top up most of the trip.
Michael Petryschuk

Mike
Just a week late but this is good news. I am contemplating pulling the head off mine this winter. I should have put in valve guides the first time.

Rick
Rick Crawford

If it's not done yet, time for a skim job,Rick
DON KELLY

That is a thought Don...THX
Rick
Rick Crawford

Better yet, buy one from Ted already done.
DON KELLY

Don
$$$ with exchange ??
Rick Crawford

Call and ask. The exchange rate is almost = now. I bought mine 10 years or so ago
DON KELLY

This thread was discussed between 12/09/2010 and 29/09/2010

Triumph TR6 index

This thread is from the archive. The Live Triumph TR6 BBS is active now.