190e 2.3-16 Head rebuild? - PeachParts Mercedes-Benz Forum

jskibo · #1 09-09-2006, 01:36 AM

OK, bad day so far....

I stopped to get gas and the 16V was running fine. Tried to restart it and it cranks forever, finally catches and sounds like a diesel (I have one of those too). Horrible rattling sound, idle is all over the place and no power. Had it taken down to my indy, he started it and shut it down right away, thinks it skipped a tooth in timing and doesn't want to run it until he can get time to remove the valve cover.....so

If I'm going to pay labor to pull the head I would rather just swap it with a rebuild. Anyone know what Flying Tiger is getting for their 16v heads?
Any other good place for a quality rebuilt 16v head?
Ideas on cost?
Anyone have a valve job (guides, valves, seals, etc....) done locally? What did it cost you?

I'll be in Saudi for the next 3 weeks (business) and was hoping to get this done before I return as I'm scheduled in for Soda blasting the whole car and a repaint in October.

jhodg5ck · #2 09-09-2006, 07:31 PM

I send all my machining to a fellow in NY. He's been machining MB engines for 30+ years and his work is Always spot on perfect.

If you would like his # feel free to drop a line.

Jonathan

t walgamuth · #3 09-10-2006, 09:24 PM

i dont see why he would have to pull the head to correct a skipped timing chain. am i missing something?

tom w

jhodg5ck · #4 09-10-2006, 09:36 PM

If he jumped time his valves and pistons made friends unless he's Really lucky..

Jonathan

t walgamuth · #5 09-10-2006, 11:03 PM

oh yeah.

even if it just skipped one tooth?

tom w

jhodg5ck · #6 09-10-2006, 11:58 PM

depends..not sure how many degrees of room one has on a 16V.
Have yet to see a jump w/ only 1 tooth.

Jonathan

#7 09-12-2006, 08:19 PM

i've heard metric motors charges roughly 600 for a rebuild including guides and seals. If you trashed a valve (or 16), then the price could be dramatically more.

jskibo- How old is your timing chain? Do you have the updated tensioner?

Jonathan-Could you send me your friend's number? I think my 16v has a burned valve. I'm toying with doing the R+R work myself.

cheers,
dan r.

john affleck · #8 09-23-2006, 04:48 AM

You can re-seal the valves yourself at home. If you're not wealthy and you feel like removing and re-placing the head; then you might llke to do this. R&R the head is far more demanding than resealling the valves. Why do you want new guides? Maybe theres no need for this. Unless the end of the exhaust valve guide is burned off in the port. I've done this for the past 35years or so. Take the valves to your local auto machine shop and ask for a quote to "bead blast, kand take a minimum clean-up cut on the valve grinding machine"; this recently went up to $1.75 a valve here. Be firm in your decision, If they want to offer you the benefit of their wisdom; eg. you have to bring the head in also; blah, blah, etc. etc.; just go to the next place. They don't have any wisdom; all they have is convention and a desire to make the bill as high as possible. When you get the valves back; they'll look like new. the exposed surface of the steell forming the seat, is new. Grind the valves into the seats using permatex brand water based valve grinding compound and an electric drill; the drill goes on the stem of the valve while it's inserted in the head and you then pull the compound laden valve into the seat, lightly and run the drill. Make many small movements off and on the seat so the abrasive can feed into the worksding area. Put the drill in reverse for a few seconds at the end. Intake valves only take a 6 seconds or something. You're fixing the seat, now, as well as guaranteeing a perfect seal, and an exhaust seat with little black pits in it will need more work. small spots can remain. The finish status is an even gray band on the seat and valve. If the seat doesn"t cut allthe way around the circle; it's shifted in the head and the head will have to go in for a seat replacement. It's usual to wipe the valve and seat with paper towels after the first 5-6 seconds of grinding and inspect the work. repeat if necessary; almost always the intakes will be finished at this first check. The fine grooves that go around the valve and seat from the grinding operation can't be improved on for a gas tight seal. A fairly low speed hand drill is what you want; not a real screamer. I don't know what your tappet arrangements are; but at the worst you may have to sort the valves for length and butt grind some to achieve valve lash;(in the case of bucket tappets). Common sense will see you through. Off course, if you're burned exhaust valve is badly damaged on the seat or shows signs of being cooked; you'll have to buy another one. The head gets washed thoroughly with dish soap and water, paper towels poked through the guides a little brush if you can find one; then do it again. Spray with wd40 asoon as you blow the water off. Clean every head bolt thread with a tap. Check the head for flatness with a steel straightedge. If it's not flat; post again and I'll tell y ou how to fix it at home. This is not a compromise proceedure and it will last as long as any other valve job. Naturally this flies in the face of conventional wisdom, which includes items like the little stick with the suction cup on it; and machinists will be horrified. It's kind of a test really to see if you like to think for yourself. There are people in Calif. right now driving pickup trucks I did dthis to 15 years ago. In almost all cases, the seat doesn't need much working; and what it does get should be the result of mating with its valve; by not giving the head to a machine shop you can save a lot of money. cheers, jack.

jhodg5ck · #9 09-23-2006, 09:12 AM

Nice idea and cost effective for those on a budget but you never mention having the guides replaced. Mercedes designed the VG's w/ replacement in mind.
In making their vavles hard and their guides quite soft w/ the notion that it's cheaper to replace a guide then a valve. On a standard benz you would be Lucky to get 200K (of highway use, around 150 if she's a city runner) out of a set of guides but on something like a 16V the rev's are higher w/ more regularity and thus harder on the guides.

Jonathan

#10 09-23-2006, 10:30 AM

Hey John and Jack,

Will this valve lapping work on an aluminum head? Also, can I replace the guides and seals in my garage as well? I can buy a head for 500 or so from a junk yard-if I can get it cleaned up by myself I should be able to swap it in for much less than having it removed by the independant and sent off.

cheers,
dan r.

jhodg5ck · #11 09-23-2006, 11:40 AM

Quote:

Originally Posted by Dan Rotigel

Hey John and Jack,

Will this valve lapping work on an aluminum head? Also, can I replace the guides and seals in my garage as well? I can buy a head for 500 or so from a junk yard-if I can get it cleaned up by myself I should be able to swap it in for much less than having it removed by the independant and sent off.

cheers,
dan r.

It will work, but it's not ideal.. Ideally you want @ least a 3 angle (pref. 5) valve job done by a machinest.

I wouldn't try putting in guides...Wouldn't even know where to begin.

Doing this sort of work and not having something come out right is Very frustrating..by the 2nd time you have the head off you'll wish you spent the $$ to do it correctly the first time.

I have a set of 560 heads sitting in my garage from a fellow who tried to do them himself.. One valve is utterly Stuck in the guide.

Jonathan

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