Sat Dec 20, 2003 9:14 pm
I just put a resurfaced head on my cub with a new gasket and torqued the bolts in the right sequence, but notice air bubbles coming from the gasket( from antifreeze I spilled). Now the tractor stalls under a load or if I throttle it too fast (loosing compression?). I first tightened up to 45 ft lbs, then went up to 50 ft lbs to see if that would stop it. Any suggestions to my next step?
Sat Dec 20, 2003 9:19 pm
Did you torque the head in gradual steps or did you go straight to 45? I'd run it for 20-30 minutes and re-torque to spec. Then re- check after a couple or so hours of run time.
Sat Dec 20, 2003 9:46 pm
Bigdog is right on. I wouldn't try any more torque on the bolts...some of the bolt holes in the block are weak and can be easily damaged by over-torqueing. Was the deck on the block in good condition? Have you ruled out cracks in either the head or block?
Sat Dec 20, 2003 11:21 pm
Also, many people use Kopper Koat as an additional sealer on the gasket when they install it.
Sat Dec 20, 2003 11:31 pm
Yes I did gradually torque the bolts down. I'll try running it tomrrow and recheck.
Sat Dec 20, 2003 11:33 pm
I had the head magnafluxed when I resurfaced it, and it was fine. As far as the block I'm not sure about a crack. I was blowing white smoke and the oil dipstick had a milky deposit on it. I was told that meant antifreeze was getting in, so I changed the head gasket. Also, when I changed the oil, a small amount of antifreeze came out of the oil filter drain. After replacing everything I don't have anymore white smoke.( only ran 15 minutes)
Sat Dec 20, 2003 11:38 pm
As far as your other point, I didn't spend alot of time on the engine block surface. I did run a razor blade acrossed it and then went over it with a wire brush in my drill
Sat Dec 20, 2003 11:41 pm
I did not use anything as far as a sealer goes.
As far as the gasket, is there a right side up rule? I was told to keep the writing up when installing.
Sun Dec 21, 2003 8:35 am
When I put the head back on my cub it did the same thing, I used a sealer with the gasket and it stopped leaking.
Sun Dec 21, 2003 10:22 am
Don't know if there is a right side up rule, but I always went with the printing up.
Sun Dec 21, 2003 1:26 pm
Well I ran my cub a little longer today and it is definitely leaking small bubbles of antifreeze around the gasket. It also blew some white smoke again. I guess I'll take it apart again and make sure the engine surface is OK and try sealer.
Will the gasket be OK to reuse, or should I get another?
Sun Dec 21, 2003 2:52 pm
I have never felt very comfortable reusing a head gasket, but I have known of quite a few people doing it and it working OK. One question though, if you add sealer to a used gasket and it still leaks, what do you do next? Do you have another problem to chase down or do you then try sealer on a new gasket?
I would suggest that if you want to reuse the gasket, remove the head by reversing the normal head tightening sequence. Just crack each bolt a little, then repeat the pattern going maybe a 1/4 turn at a time until the bolts are all loose. Otherwise, you will probably deform the gasket when you loosen the head bolts.
Sun Dec 21, 2003 3:33 pm
You make a good point about a used gasket. Ill get a new one tomorrow along with some sealer.
You mentioned taking off the gasket a 1/4 turn. How far do you turn to put one back on?
Sun Dec 21, 2003 5:30 pm
Iâ€™ll try to not start a war hereâ€¦
We have hashed over this a number of times on the ATIS tractor list over the years. Everybody has their own ways of doing things and that is as it should be. Butâ€¦ It is as simple as thisâ€¦ in my shop ALMOST NOTHING goes together dry. I have not done thousands and thousands of jobs but I have turned wrenches for $$$ in the past and still do now and then but Iâ€™m just a lot slower now.
I have â€œneverâ€ had a head gasket fail that I installed. Never. I have also never put a head gasket on dry and have no plans to ever do so. I firmly believe that having something on there is generally more important than what is used. I do not like products that are like permanent glues like the old original Permatex products were. I am kind of partial to the copper-cote type of products but have used many other things including from Hi-tack type products all the way to a simple brushing with grease. I think it is important for the mating surfaces to slide against each other. As you tighten a head down for example that gasket has to move around a tiny bit as it is compressed. I believe that almost anything that provides a bit of lubrication to help it shift into place will help it form into the proper shape. You have to think like a molecule.
I never put bolts together dry, especially head bolts. I clean each bolt on a wire wheel and make sure the holes are clean. I dip the bolt in oil just before I put it in the hole and I want the bottom of the bolt head and the top of the cylinder head where the bolt head seats both lubed. When I torque a head down I do it in at least about 5 steps. On something like a #$%& CUB the first pass might only be 5 # of torque but always in the pattern. I wouldnâ€™t dream of going to 45 # on the second or even third pass. Re-torquing after running enough to warm the engine up is just automatic.
I like to use a huge fine cut flat file to lightly draw-file both the head and the top of the block. Not to remove material but to be sure there are no unseen burrs or bumps that a visual inspection might miss.
Of course we are talking old tractors here. I realize that a lot of new cars and trucks call for a lot of special techniques and they should be observed in those applications.
Sun Dec 21, 2003 8:22 pm
How far do you turn to put one back on?
You reinstall by torque, not amount turned. I think Farmer covered that quite well, probably with more attention to detail than done by most.
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