Author Topic: Need Engine Help (Read 2995 times)

Gunslinger · « **Reply #105 on:** March 05, 2007, 04:30:03 PM »

Question: these new seals do not have springs, just the metal clip at the top. Should I replace those with the springs or leave as is?

The new ones look completely rubber, while the old ones look like they had to be stamped on. There is a noticable difference in the "grab" of the new ones, but probably cause they are brand new. The existing seals just look cheap and worn. I ruined one of them not knowing that the metal portion of the old one had to be removed as well and wore out the new one by trying to put it over both the guide and the seal. (noobie move)
Old one

New one

The fellpro kit I got has about everything I need. It just sucks that I had the head off at about 10AM but didn't get the kit till about 330PM.

Coshy · « **Reply #106 on:** March 05, 2007, 06:26:12 PM »

The valve guide seals are merely caps held on by friction (the ones I've replaced at least). The springs around the tops of the old ones provide that friction, the metal bands on the new ones perform the same function. The 'glue' you are seeing may be silicone sealant, or just accumulated crud. I cant tell from the pics.

If you clean the (for lack of a better term) nipple where the valve stem comes through, you should be safe applying a small amount of silicone sealant at the base, just enough to hold the seals in place, but be sure its a hi-temp one that is impervious to gas and oil. To be honest you shouldnt need it. The caps should fit snugly on the nipple as well as the valve stem itself.

I would avoid the temptation to squeeze the metal band around the nipple, that could distort the rubber and put you back where you started.

Have you had any other opinions about oil/coolant? I'm curious what others on more automotive boards might be suggesting.

doom · « **Reply #107 on:** March 05, 2007, 06:45:47 PM »

maybe u might have flooded it, or u just might need some anti-freeze

Gunslinger · « **Reply #108 on:** March 05, 2007, 07:39:47 PM »

Quote

Originally posted by Coshy
The valve guide seals are merely caps held on by friction (the ones I've replaced at least). The springs around the tops of the old ones provide that friction, the metal bands on the new ones perform the same function. The 'glue' you are seeing may be silicone sealant, or just accumulated crud. I cant tell from the pics.

If you clean the (for lack of a better term) nipple where the valve stem comes through, you should be safe applying a small amount of silicone sealant at the base, just enough to hold the seals in place, but be sure its a hi-temp one that is impervious to gas and oil. To be honest you shouldnt need it. The caps should fit snugly on the nipple as well as the valve stem itself.

I would avoid the temptation to squeeze the metal band around the nipple, that could distort the rubber and put you back where you started.

Have you had any other opinions about oil/coolant? I'm curious what others on more automotive boards might be suggesting.

Actually what I thought was glued in was just the rubber portion of the old seal. When I removed one I just pulled on the rubber with a pair of needle nose. The thing that it attaches to is metal, as shown in the pic. I didn't realize that the entire thing came off. The new ones seem MUCH better as the old ones were very brittle.

My subject matter expert from the 4x4 board says he's never seen a HG failure on a 4.0 without having the radiator "puke it's contense out."

He doesn't seem to think the mixture of oil and coolant was that bad.

I went ahead and put the head back on as I'm running out of time. I gotta get the engine put back together and the exaust done tomorrow. I go back to work sunday but have alot of stuff to do between now and then.

Excel1 · « **Reply #109 on:** March 06, 2007, 05:17:52 AM »

Over heating is probably the main cause of head gasket failure but it's not the only cause

It might not apply in this situation, but head bolts that haven’t been torqued to spec or have worked loose can cause head gasket failure and often a warped head

lazs2 · « **Reply #110 on:** March 06, 2007, 08:41:53 AM »

I would strongly suggest that you have the head rebuilt (valve job) at a known reputable shop... It will save you money and grief in the long run... If the head is warped you simply need to have it surfaced... if it is so bad that it can't be surfaced or... it is cracked and the magnaflux shows that.... the rebuilder probly has a reasonably priced core.

There are lots of reasons valve seals fail and lots of different types of seals.. usually.. if the seals have failed the guides and/or valves are worn so new seals will not do the job.

I have been broke and tried to mickey mouse things back together too many times myself including hand lapping valves and knurling guides... all kinds of make do fixes.. I simply feel you will be better off getting a professional valve job.

lazs

eagl · « **Reply #111 on:** March 06, 2007, 09:12:17 AM »

And realize that what one mechanic considers a "valve job" isn't the same as the next one... One will charge you to simply grind the valve seats, and the next will re-do the valve guides, work any alignment problems, replace bent valves, check pushrods, spring tensions, and put the whole thing back together properly using new bushings/bearings, the right tolerances and torque specs, etc.

Getting the head squared/surfaced is sort of the same... Some guys can work magic and true up a mildly warped head or match it to the block, but others will just slap on a thick coat of form-a-gasket and hope it lasts longer than their 30 day warranty. Find out exactly what work they plan on doing. Don't trust the generic job description.

lazs2 · « **Reply #112 on:** March 06, 2007, 02:29:47 PM »

no rebuilt head would not include a magnaflux of the head and a check for straight and checking the valves/valve guides.

lazs

Gunslinger · « **Reply #113 on:** March 06, 2007, 02:51:34 PM »

Either way the head went back on today. I followed the book and checked it best I could with a strait edge. I bought a torque wrench and followed the instructions on torqing the sucker down. All the rockers went back on. I almost had a nightmare when the LAST push rod fell through but was able to retrieve it with a magnet.

I spent the rest of the day cutting out my exhaust. While doing so I noticed my tail pipe had a severe bend in it, probably from the accident it was in a year ago.

I really wish the head pipe I ordered was here cause I'm ready for it as I'm not sure what's going to happen when I cut that end of the CAT off.

I'm hopeing to have the exaust done by tommorrow so I can finish putting everything under the hood back together then start on replacing the carpet.

After the jeep is done my new pool liner should be here and it's off to work on that.

Wow I love vacations.

Bronk · « **Reply #114 on:** March 06, 2007, 02:56:06 PM »

Gun I know it's a bit late but invest in one of these if you like doin it yourself.

http://www.stant.com/index.cfm?location_id=183

Can help narrow down the problem when diagnosing.

Bronk