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Valve problems; May have found our problem
Topic Started: Feb 13 2013, 10:16 PM (2,521 Views)
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OK.

You'll need a vertical mill to surface the head. Remove a minimal amount. 0.005" is usually enough.

After you clean the head, you can remove the valve guides by heating the head in an oven to 250 degrees F.

You'll need a Kent-Moore P/N J37968 valve guide removal tool. I'm not sure how much force is required to remove/install valve guides. My machind shop gets to do that for me. Put on the J37968-3 collar to install the new guides to the correct depth. The basic + -3 tool can also be used to install the valve stem seals. Don't forget to put on the lower spring washer prior to installing the valve stem seal. (The tight winding on the spring goes towards the head)

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You need to check the valve to guide clearance.

The FSM diameter for new intake valves is 0.2148" - 0.2157".

The FSM diameter for new exhaust valves is 0.2142" - 0.2148"

The nominal ID of the valve guide is 5.5mm

The FSM new clearance for intake valve to guide is 0.0008" - 0.0022".

The FSM new clearance for exhaust valve to guide is 0.0018" - 0.0028".

You'll need a fine stone hone to finish the ID of the valve guides.

http://www.cylinderheadsupply.com/kl2424.html

You'll need a set of precision ball gauges like I have to measure the ID of the valve guides.

http://www.precisionballs.com/all_ball_gages.php#B

Hopefully, you have the equipment to repair your valve seat surfaces, if they need it.

There's a whole lot more in the Factory Service Manual about engine repair. I'm not so sure Chilton or Haynes have such detailed information.

FSM's are available on Ebay, if you don't have one.

Good luck!

GG
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wildhair


Dude you are awsome.
Maybe this one is best left up to the pros.
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wildhair
Feb 23 2013, 11:42 PM
Dude you are awsome.
Maybe this one is best left up to the pros.
I wasn't trying to talk you out of it, kinda . . . ^o)

For what it's worth, every exhaust valve that I've ever seen is stainless steel. Even the cheap ass ones on Ebay. Take a magnet and see if it sticks to your "standard" exhaust valves. I'm 100% sure it won't.

Also, while you have the head off, check the cylinders for taper and out of round. I don't ever see much taper. But, they do get out of round. The factory service limit for out of round and taper is 0.0038". Anything more than 0.0025" out of round, and I'm getting the block bored to the next size. A lot of the engine cores I get back have at least one cylinder that's 0.0050" or more out of round.

Anything you put together will run. The closer the tolerances are to new, the longer it will run.



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wildhair


I wasnt trying to be a pain in the a$$.
I do apreciate honest and brutal answers.
In your experience would a bad injector cause the exhaust valves to cook?
Ive read it was due to everything from a bad PCV valve to clogged EGR ports.
So far the only thing that makes sense is the injector.
I have checked all of the "known" causes of burnt valves and cant find anything wrong.
The only thing I could find was the injector not having a good spray pattern.
Im also fairly sure it was the original injector and has over 260K miles on it.
The new injector runs alot better than the old one but with burnt valves its hard to tell if that was the only problem.

Edited by wildhair, Feb 24 2013, 12:18 AM.
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No problem, wildhair. Just trying to help.

Bad injectors cause the engine to run bad. Blue Rhino can clean injectors if you want to send him one. I doubt if this is your problem.

I've read all the speculation and conjecture of why exhaust valves burn. It didn't really make much sense to me. My 1990 has no EGR valve. I've toasted my share of exhaust valves. My PCV valve has always been clean. The forum truth about burning valves associated with EGR valves and PCV valves, in my mind, has been reduced to myth.

When the engine has excessive blowby from worn piston rings, the oil becomes contaminated with carbon. Never mind the minimal additive package and higher ash content of most engine oils.

When this carbon finds it's way into the valve lifters, the hydraulic units inside the valve lifters become clogged and are no longer able to bleed down. This allows the intake and exhaust valves to remain open ever so slightly. No problem for the intake valves, but the exhaust valves become eroded (burned) from the continuous flow of hot gas when the valve is nearly closed. If your lifters do not have any springiness to them when you push on the plunger, they need to be cleaned. If your engine is producing excessive blowby, they will need to be cleaned again at some time in the future.

If you notice any rough idle when you first start the engine, this is the first sign that the lifters are sticking. The rough idle will go away, of course, but it won't be long before the exhaust valves burn.

The other problem associated with excessive blowby and carbon in the engine oil is that the oil pressure relief valve in the oil pump will stick. When it sticks, it will stick in the high pressure position, causing excessive pressure to the head and the lifters. Combine excessive oil pressure with a high carbon content in the oil, and your lifters will fail to function properly, and your exhaust valves burn.

You've probably read that replacing the rings when you do a valve job is a good idea, also. This is true. However, a good rule of thumb that I use is the ability to see the factory hone marks in the cylinders. If the factory hone marks are still visible, the cylinders, when measured, are no more than 0.003" out of round at the top, and installing a set of new standard size (EVE gap the tightest) rings results in a quality repair that will last for a very long time. Cylinder bores that are 0.005" out of round produce excessive blowby when re-ringed with standard size rings. I see it when I take apart core engines. Someone attempted to re-ring a worn out engine. It burned valves. The lifters have no springy action. The oil pressure regulator valves are stuck in the oil pump case.

Contact these guys before you order any standard rings to make sure they have the Evergreen (EVE) rings available. Otherwise, you'll get NPR rings. The NPR rings gap 0.003" looser than the EVE rings.

http://www.ebay.com/itm/250743961619?ssPageName=STRK:MESINDXX:IT&_trksid=p3984.m1436.l2649

Check your cylinder bores for dimension and out of round. That may be your source of your problem.

I'm not trying to talk you into spending a whole bunch of money on engine repair. I've done some of the most crap ass engine repairs to my own engines, knowing that eventually something's going to go wrong, usually burned exhaust valves. $300 or less in parts will get you many thousands of miles down the road. It may be 5,000 miles, or it may be 85,000 miles. It doesn't matter. Just as long as you can do the work, and are ready to do it again. You get from Point A to B and back for what ever reason you need to get there. Anything you put together will run. For how long? Who knows . . .

GG


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wildhair


Thanks again for the info. :thumb
I'll do some measuring and check the lifters for some spring back.
Now that you mention it the whole lifter thing makes alot of sense.
The lifters needed some attention when the head was off the last time.
The valve guides are shot "the valves wiggle some"so I guess its a good thing I ordered them also.
How would I go about checking the oil pump ?
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wildhair
Feb 24 2013, 09:38 PM
Thanks again for the info. :thumb
I'll do some measuring and check the lifters for some spring back.
Now that you mention it the whole lifter thing makes alot of sense.
The lifters needed some attention when the head was off the last time.
The valve guides are shot "the valves wiggle some"so I guess its a good thing I ordered them also.
How would I go about checking the oil pump ?
You're welcome.

Here's how I clean oil pumps.

http://geometroforum.com/single/?p=593694&t=4623367


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dayle1960
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Fastest Hampster EVER

I hate your guts, GG. :evillol You are way tooooooo smart. :thumb

Glad you took the time for a wonderful write-up. Great nuggets of information were contained within your comments.
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wildhair


I checked the lifters today none had the slightest spring to them.
I tore them apart and cleaned them with an ulratsonic cleaner and reasembled . They all seem to have a fair amount of spring.
From looking at the parts they look like they are supposed to pump up to size and not bleed off. So wouldnt they be pumped up too hard to be springy??? :hmm I dont realy know weather or not to trust them.

What do you think GG?

I know the 4.0 answer would be to replace them but they work smooth and have what seems to be enough spring tension.
Oh I also checked the exhaust valves with a magnet as you had suggested :thumb and they are in fact ss valves. ^o)
I thought ss would have cleared up the whole burning valve problem, but it seems like there is no quick fix.
Havent checked the cylinders yet, but will do.
Thanks for the link to your How to Clean a G10 / G13 Oil Pump.
You did a nice job putting it together with lots of pictures. ;)

OOps forgot do you think if the valve guides are warn so the valve wiggles a little this would cause the engine to use a little oil and
be the source of the carbon contamination you explained?
Edited by wildhair, Feb 25 2013, 10:53 PM.
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Scoobs
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:D

Youll have more problems if you replaced them.... youll have to pull the new ones apart and fix the shit they do with them anyway Lol. Ive never had any issues with rebuilding them.
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wildhair


Thanks scoobs. always good to get another opinion from some one who has alot more time under the hood than I do.
When testing them would you say they were springy fresh out of the car?
Or were they solid as a rock?
All of mine were (prior to cleaning) solid.
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wildhair
Feb 25 2013, 10:41 PM
What do you think GG?
:hmm
wildhair
Feb 25 2013, 10:41 PM
I checked the lifters today none had the slightest spring to them.

I tore them apart and cleaned them with an ulratsonic cleaner and reasembled . They all seem to have a fair amount of spring.
From looking at the parts they look like they are supposed to pump up to size and not bleed off. So wouldnt they be pumped up too hard to be springy??? :hmm

I dont realy know weather or not to trust them.
This lack of springiness is probably why your engine does not run for long. Cleaning lifters with an ultrasonic cleaner it the best. They will have spring when they are properly reassembled. As long as they remain clean in service, they will bleed down. I have seen a high mileage (184,xxx miles), unmolested G10 engine that still had springy valve lifters. The engine was very clean inside. I can only speculate that the engine still ran well when the car hit the salvage yard due do death from frame horn rot. I have cleaned many sets of lifters. Cleaned lifters, when properly cleaned and reassembled, will work well for a long time.
wildhair
Feb 25 2013, 10:41 PM
I know the 4.0 answer would be to replace them but they work smooth and have what seems to be enough spring tension.
New valve lifters are made in China by two companies that I know of. Trans Industrial Co., Ltd. in Chengdu , Sichuan, China (P/N TSVL-042) and Rui'an Hanous Trading Co., Ltd. in Wenzhou, Zhejiang, China (P/N HN10106). Both of these companies produce a very precision part. Both of these companies are certified to ISO 9001:2000 and ISO/TS 16949. The lifters are assembled with a light preservative oil. I use a "C" clamp Vice Grip (welding Vice Grips) to squeeze the lube out of the lifters prior to installation. It's 4.0, but they're also $61.99 for a set of 6 on Ebay. It doesn't matter how much you pay, or who's name is on the package, or where they claim they're made, they all come from China. Mainland China (Thank you, RMN.)
wildhair
Feb 25 2013, 10:41 PM
Oh I also checked the exhaust valves with a magnet as you had suggested :thumb and they are in fact ss valves. ^o)

I thought ss would have cleared up the whole burning valve problem, but it seems like there is no quick fix.
Right. Non-magnetic stainless steel. I'd have to send an intake valve to my Cousin, Dr. Hoopie, M.D., the Rocket Scientist, to get spectrum analysis done, but I believe all of the intake valves are some variety of magnetic stainless steel. I'm not highly inclined or motivated to do so, since there's no widespread problem with intake valves.

What is really important is to measure the stem diameter of your intake and exhaust valves, no matter where you get them. A parts vendor will typically not spec parts prior to shipment. An good engine builder will always spec parts prior to assembly. Keep in mind, there's two general categories of manufacturing in China. The really, really good, dialed in, A-OK, Squared-Away kind of companies, and the companies that make toys for Happy Meals. Measure your valve stems. The diameters are in the Factory Service Manual. You should see diameters that are within a couple of 1/10,000" of the max diameter. I used to use "Sealed Power" exhaust valves. Made in South Africa, China. Stainless steel, good stem diameter, and a good fit. One day, I noticed a difference in appearance. There was a different part number etched on the stem. I measured them. They were 0.0002" below the minimum diameter. I did not use those valves. I got a refund from Rock Auto, and tossed them in the recycle bin. My favorite "Osvat" intake and exhaust valves are made in Italy. Right. Italy, China. They're really good Italian parts, from China.

Anqing Xinyi Auto Parts Co., Ltd., Anqing, Anhui, China. "For serving clients better, we have registered some brands as our own, and we have the brand proprietorship of OSVAT, PAGZD, QUEEN and NPW in China."
wildhair
Feb 25 2013, 10:41 PM
Thanks for the link to your How to Clean a G10 / G13 Oil Pump.
You did a nice job putting it together with lots of pictures. ;)
^o) That brings back memories. It's so much easier to clean oil pumps in an ultrasonic cleaner.
wildhair
Feb 25 2013, 10:41 PM
OOps forgot do you think if the valve guides are warn so the valve wiggles a little this would cause the engine to use a little oil and be the source of the carbon contamination you explained?
Valve to guide clearance can not be reliably checked using the wiggle method. An in spec clearance will have a little wiggle. You need to use a ball gauge and micrometer to determine the ID of the guide, or a set of single size precision balls, and do the math to determine what clearance you have on your installation. Your machine shop has the measuring equipment to check the guide bores. It would be interesting to see what the ID of your OEM valve guides are, if the machine shop is so inclined to measure them for you and do a valve to guide clearance check. Just make sure your valve stems are in spec before you drop them off, or have the machine shop check the diameters and call you if they're below minimum diameter. Very important. Do not use any valves that have stem diameters that are not within spec. Contact your vendor for a refund if this happens.

Also, very important, some machine shops have a set of aftermarket specs. Print them a copy of the FSM dimensions and limits page and take it in with your work. Highlight and circle the numbers. Talk to the boss and make sure the guy who does the work gets the memo. Suzuki built heads using these dimensions and clearances. You should expect no less.
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wildhair


Thanks for taking all the time to answer my questions, I know your a busy guy with your engine buisness.
You sir are a true freind to this community. ;)
I love my little Geo and want to keep the darn thing running forever. :wub:
All the guys make fun of me untile they ask about the mileage, But then again Im 6'3'' 250lbs. I gues it is a little funny ^o)
Even running on 2 cylinders it was getting 39 mpg.
My compression numbers were
1--90 psi
2--3 psi
3--120 psi
It didnt have alot of power but did get me to and from work.
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wildhair


Just out of curiosity do the 1.3L motors burn valves?
If not why?
Are the lifters some how better?
I was just thinking I had not read much about them burning valves.
If the only thing that is different is the lifter, this would support GG in that
burnt valves are the result of lifter failure not PCV or EGR problems.
At the risk of sounding like a dumb a$$ is there a suitable replacement
for the factory spec that could be experimented with.
Edited by wildhair, Feb 28 2013, 09:00 PM.
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wildhair
Feb 28 2013, 08:44 PM
Just out of curiosity do the 1.3L motors burn valves?
If not why?
Do they have the same type of lifter or are the lifters some how better?
I was just thinking I had not read much about them burning valves.
If the only thing that is different is the lifter, this could support GG in that
burnt valves are the result of lifter failure not PCV or EGR problems.
I have heard of a G13BA engine or two burning an exhaust valve. Very rare. My 4 cylinder engine has 183,000 miles. It has never been overhauled. It uses a quart of oil every 1,200 miles, and has for the last 70,000 miles.

The G13BA has hydraulic lifters. They are of a different design.

From my experience with the G10 and G13BA engines, I'll say that the G13BA runs a lot cleaner than the G10. I don't know why.

I can run the same oil in my 4 cylinder for 12,000 miles with a filter change every 3,000 miles and remove fairly clean oil. My 3 cylinder oil is much darker than the 4 cylinder oil after only 3,000 miles.



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