Broke A Valve Spring Yesterday

[thomastractorsvc]

Yesterday I was coming back from a ride in my B61, and sounded like the exhaust started leaking, and I picked up a miss, was not running to hard about 2k and 50 mph, did not loose oil pressure, no leaks drove about a mile back to the house and pulled into the shop grabbed the head bolt studs and all seemed tight. I scratched my head for a minute and then started it back up, poking around the engine it sounded like the noise was coming from the front valve cover, reached down on the pump and shut the motor off went in side.

This afternoon pulled the valve covers off and found a broken exhaust spring on the front cylinder, Keeping my fingers crossed that it did not drop far enough to hit the piston as the valve still moves up and down easily.

Is there a place to source the head gaskets, valve springs exhaust and intake gaskets and head bolts as if I take the top apart I should change them or do I now have a boat anchor?

[Freightrain]

Might get away with just pulling the spring and just replacing it. As long as it didn't bend the valve. Have to diagnois it more.

[thomastractorsvc]

I was hoping to replace without pulling the head, that's something you can do with the 673?

[39 Baby Mack]

You should be able to bring the piston up to T.D.C. this will hold the valve from falling into the cylinder.

You would have to fabricate some sort of spring compressor.

The compressor can be leveraged off of a bracket bolted into one of the bolt holes in the head for the rocker arm pedestals.

Ron

[thomastractorsvc]

That's what I was thinking, now to find a spring!

[thomastractorsvc]

Took the front bumper off to wrench over the engine, got up to TDC, removed the rocker arm assembly and took the spring keeper out and pulled the springs, both inner and outer were broken.

[thomastractorsvc]

Video of yesterdays drive, around minute mark 4:50 is when the spring broke http://youtu.be/9fZxTCGHioo

[Freightrain]

Well, at least you got it apart. Now to find a spring.

The thing I would wonder is if you could find a set and replace them all now. It could be a fluke or it could be the start of something.

[thomastractorsvc]

I looked at the rest and compressed and turned them, they all seem to be good with no cracks/rust or bad spots, couldn't see all parts of the inside ones that good but was able to turn them and compress so I know they are not broken.

None of the others have any coke or rust on them. I contacted a couple different places and Watts about new springs, not available new that I could find.

Looks like it will be a used one.

[rsb502]

Just out of curiosity how different are the E6 2 valve springs from a 673? PAI lists 2v springs and they may actually have them for a 673 and just not list them in their parts book, PAI spring kit p/n is ESS-8950 it includes one inner and outer spring and a rotator the lock is an EVL-8210. cxall PAI and see if they offer them 770-822-1000. Did you try Winrock Truck Parts? 800-676-0052 ask for Bill but John or Casey can help, also try Southeastern Equipment at 706-798-7500 they have a ton of 707 and 673 parts and do rebuilds. Good luck.

[thomastractorsvc]

Found some on ebay (thanks Superdog), I bought two sets, that will do the entire engine.

MACK TRUCK 672 707 TURBO DIESEL VALVE SPRING RC13SA

[39 Baby Mack]

Great!

Ron

[thomastractorsvc]

Got my UPS email will be here tomorrow both sets, then I will be busy get my girl running again!

[thomastractorsvc]

Just got the springs they are new but will need to be cleaned look like they have a carbon or graphite flake to them, while I am cleaning all the springs I will soak the rotors in oil, they don't seem to have anything on them. I will wipe them and put in the oil.

I bought a large valve spring compressor not sure if that will work, if not I was flipping through the manual and it kinda showed a tool. If I end up making something I will take a picture of it.

Now to get dirty!

[39 Baby Mack]

Good luck!

Ron

[Superdog]

Found some on ebay (thanks Superdog), I bought two sets, that will do the entire engine.

MACK TRUCK 672 707 TURBO DIESEL VALVE SPRING RC13SA

230011468259_35.jpg

you're welcome,always glad to help when I can

[thomastractorsvc]

Well I ended up making two tools, one did two valves like I seen in the book, the second did one at a time, I replaced only two valve springs, the broken exhaust and intake. I suppose if I had help it would not be such a PITA to do the others but with the hood and fenders on it did not make sense to try and do the others climbing in and out turning the motor it was had to tell if the piston was all the way up on the next cylinder. So decided before I dropped a valve inside the engine I would stop while I was ahead of the game.

I did climb back and forth and was able to check the valves most were good a few were out so I did get that done, I got it all put back together. The rear valve cover had the rubber gasket so I cleaned it and used some gasket shellac and got that one good, found a couple of fuel lines that were touching with some flat spots got that taken care with some small rubber hose. The front valve cover I had to use some form a gasket, I use the copper blend on valve covers and have had real good luck with it so I did not get the truck started since it needed to cure.

[thomastractorsvc]

Got my ole girl running this morning, I let her sit and idle while the boys and I cleaned the shop, then we headed off to walmart to pick up cookies as my wife had surgery on Monday and was craven a sweet snack ( and I wanted to take her out for a drive).

When I came in to wash up before heading to the store my wife said the truck sounded good, which it really does I guess between the weak/broken valve and the other ones out of adjustment made a noticeable difference. I didn't think it ran that bad before but it sounds a lot better now. I am very happy she is running too.

[Superdog]

good deal

[thomastractorsvc]

Thanks, if the weather is good and my wife feels better, I might try and drive her over to the truck & tractor show in Platt City,MO

[countryboy5487]

Always makes you feel good when you fix teo problims at once. Especially when one you dodnt know about!

[countryboy5487]

Always makes you feel good when you fix two problems at once. Especially when one you didn't know about!