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Mazdaspeed Archive => Mazdaspeed Miata Tech issues => Topic started by: Ex36 on August 17, 2016, 06:12:44 PM



Title: About to pull head: questions.
Post by: Ex36 on August 17, 2016, 06:12:44 PM
My exhaust manifold stud project is truly out of hand, but I'd rather dig deeper and feel well-assured everything is tip-top than bail.  Given my 20% leak-down number on #2 (which my mechanic guru friend says is not necessarily alarming for a cold engine), I want to examine and swap out the head gasket.  Here are my questions:

1.  I've taken all electrical connectors and vacuum hoses off the intake and only have the timing belt and fuel rail supply line to free and then I can lift the head and intake manifold out together, right?  There's one set of wires laying between the intake and block (the 3 connectors are held by a bracket affixed to the upper timing belt cover) and I'm hoping I don't have to fish that out of there, since it's under the fuel rail, which I want to leave attached.

2.  If I have a machine shop check out the valve seats and guides, and the exhaust manifold for true, is there any relatively inexpensive work worth doing for performance gains (porting, decking, etc.?).  I've never been into an engine this deep before.

3.  Rockauto sells head bolts from Fel-Pro or Victor Reinz for $25/set.  Any reasons not to do this on a stock engine instead of the $145 ARP?

4.  What about a Fel-Pro or VR head gasket instead of OEM?

5.  I may replace the original 2005 radiator, although I'm really sick of being nickeled-and-dimed with all the replacement parts I've purchased and could do it later.  I've read plenty about likelihood of failure and alternatives.  But I haven't seen any discussion of the dirt-cheap radiators Rockauto has (like $75-85).  I know there's a MSM-specific radiator, and I know those will have plastic which will eventually harden, but are they worthless garbage?  I'm not really interested in an aluminum upgrade and happy to regard the radiator as a "wear item" (like it is on my M3).

Thanks,
Sasha


Title: Re: About to pull head: questions.
Post by: SilverMiataRacer on August 17, 2016, 06:27:58 PM
I'm just going after 4 and 5 here  JMHO

Since this is a turbo I'm make sure whatever gasket I used had been successfully used by other people with turbos.

The radiators Rock Auto has are the same part number for a turbo and a non-turbo car so which is it??  The turbo or the non-turbo version.  My take, not worth the chance.


Title: Re: About to pull head: questions.
Post by: PK1 on August 17, 2016, 09:30:15 PM
I consider myself very much a newbie with these cars but given that radiator is a topic that I have thought about myself, I'll offer you what my decision process looked like (your situation and climate may be different):

- My stock 2005 radiator seems fine, but given that it is 11 years old I decided I should change it
- Had I been planning on keeping my car stock, I would have seriously considered getting another OEM radiator for the MSM as a plug and play
- Since I will be upgrading my car at least with a FM LE (more power = more heat), added to the fact that I live in a warm/hot climate made it logical for me to upgrade the rad and fans.  I purchased the FM cross flow with their stage II fan kit.  I don't track or race the car, but my logic: I don't want to drive on a 100 degree day in traffic thinking whether or not I should be running the AC or if I should drive gingerly in fear of overheating...  This is not why I bought this car.

As a disclaimer, I haven't installed either the FM LE nor the radiator (just bought them 1-2 weeks ago, need to find time!), but given how critical cooling is and the extent of associated damage, my logic was not to mess with a cheap rad.  I would say as a minimum buy the OEM rad. designed for these cars.

My two cents...


Title: Re: About to pull head: questions.
Post by: ElyasWolff on August 17, 2016, 09:55:11 PM
1. it would be easier to take the upper intake manifold off. that way you can remove the fuel rail, injectors and wiring easier.

2. You can do some light port work at home for the price of a dremmel. Just go easy and focus on smoothing thins out rather than reshaping your ports.
http://www.mazda-speed.com/forum2/index.php/topic,32322.msg356433.html#msg356433

3. The rock auto bolts work fine for your application

4. I used this fel-pro head gasket set from rock auto
http://www.rockauto.com/en/moreinfo.php?pk=6650532&cc=1433205&jsn=373
Of the 2 they sell this one is for the MSM, it also comes with the exhaust gaskets for the turbo as well as the oil return line gaskets. Part number: HS26234PT2

If you are going to do port work you might as well lap the valves yourself. It is easy with a drill and a peice of vaccum line attached to the valve stem.



Title: Re: About to pull head: questions.
Post by: '95MSM on August 18, 2016, 01:49:11 AM
1) I would definitely do a performance-oriented valve lash adjustment while the head is off (~.008 intake, .009 exhaust).

2) I doubt that a machine shop is going to want to deal with the head with the manifold attached, so do a VTCS delete while it is off.

3) I agree with EW - lap the valves yourself if you have access to a valve spring compressor. I made a gizmo that goes between the valve spring compressor and the top of the spring retention plate. It has windows that allow the keepers to be plucked out or settled into place. I don't know how I would go about disassembing and reassembling the valves & springs without it. It might be possible...

4) My gut says the most restrictive area in the intake manifold (other than at the VTCS half-butterflies) is the mouth of the plenum. The EGR passage is the tunnel at the lower left & can be removed if you have the tools (die grinder). This would be a tiny gain, but tiny gains add up.


Title: Re: About to pull head: questions.
Post by: Graz16 on August 18, 2016, 11:26:58 PM
Hi Sasha,

I suspect that it gets at least as warm in SoCarolina as it does in SoCal. Please consider the water pump and the timing belt replacement. I know it is more work and "project creep" is a real issue. But, if those haven't been done, You will have to do them eventually. Why not have an engine closer to OEM specs?

Just my 0.02


Title: Re: About to pull head: questions.
Post by: Ex36 on August 19, 2016, 02:27:09 AM
A new TB and WP (along with the various tensioners and seals) are sitting on the garage floor, so I'm definitely doing them!  Good luck sorting out your cooling issues. 

Thanks for the input everyone.  It sounds like I've got more digging to do.  Maybe the car will be ready for the fall, which is much more glorious here than the summer.


Title: Re: About to pull head: questions.
Post by: Ex36 on August 28, 2016, 06:27:26 PM
Had to kick the started to break the crank nose bolt free--that sucker was on there.  Now do I just grab onto the Woodruff key with a needle nose in order to get the pulley off (10mm bolts are off as well)?


Title: Re: About to pull head: questions.
Post by: Qwimby1 on August 29, 2016, 01:21:55 AM
I'm at the radiator-replace stage now also and was considering the FM crossflow and definitely the FM intercooler as I work toward getting this car track ready.  With the intercooler I'll have almost a full LE kit.  I've put 80,000 miles on the car in Florida, much of it in 90-degree plus heat with the air on and never had a cooling problem.  One of the FM guys thought, with my power setup, I'd be just fine with another OEM radiator and their intercooler.  If I get another 80,000 miles out of the new plastic rad I'll consider it a good buy.


Title: Re: About to pull head: questions.
Post by: '95MSM on August 29, 2016, 03:11:41 AM
Had to kick the started to break the crank nose bolt free--that sucker was on there.  Now do I just grab onto the Woodruff key with a needle nose in order to get the pulley off (10mm bolts are off as well)?
Maybe someone with more recent experience will answer, but IIRC, the key IS a woodruff type, which is a crescent shaped key that sits in a crescent shaped hole. The pulley hub has to come off the crank, then the key can be removed. Tap all around the perimeter of the pulley or hub and try to walk it off. If that doesn't work, you'll need to use a puller. (If you have a puller, jump to that step and forget the tapping.) If you haven't used a puller, post it here and someone will describe the process.


Title: Re: About to pull head: questions.
Post by: Ex36 on August 29, 2016, 03:26:16 AM
It looks like there's still a metal collar or flange within the center of the pulley that overlaps the pulley, so it looks kind of like the key has to come out first, and then this insert with the flange, and then maybe the pulley will come free?  My reading made it sound like once I removed the 4 small bolts and then the monster crank bolt I would be golden.  TBH, it's strange to me how much there is written about the TB change (Keith's book, YouTube DIY's, etc.), yet this part is not clearly described or shown.


Title: Re: About to pull head: questions.
Post by: SilverMiataRacer on August 29, 2016, 09:54:42 AM
The key is an asymmetrical rectangle shaped part.  It is VERY important it be replaced in exactly the correct orientation or it leads to crank nose failure. 

Remove the 4 bolts and take off the big pulley and timing disc paying attention to the position of the disc.  Remove the bolt and remove the pulley boss and pay attention to the directional fit of the key.  Smart money says to replace the key, loctite the bolt and torque and replace the 4 bolts and CAREFULLY torque them as they have surprisingly low torque settings.


Title: Re: About to pull head: questions.
Post by: mr_hyde on August 30, 2016, 01:41:34 AM
The two accessory bolt pulleys that are attached with the four 10mm head bolts can stay together with the rest of the assembly.  The whole thing should slide off the crank once the timing belt is loose.  I just did an early NB timing belt and once the big 21mm bolt was out, the rest just came apart very easy.  They key even sat on the crank.  If you have more corrosion than that, you might need a puller but usually the OEM pulleys come right off.


Title: Re: About to pull head: questions.
Post by: Ex36 on August 30, 2016, 05:15:08 PM
Thanks.  With the 21 mm crank nose bolt out, as well as the 4 x 10mm bolts, I gather the pulley that drives the 2 accessory belts should just come off.  There must be corrosion on the back side "gluing" it in place.  Are you suggesting that if I loosen the TB tensioner,  those 2 accessory pulleys will come off with the toothed timing belt pulley behind all as a unit?


Title: Re: About to pull head: questions.
Post by: mr_hyde on August 30, 2016, 11:25:50 PM
Yes. You might need to take the timing belt actually off the cam gears to make sure it is free but the whole thing should come out. A few whacks with a rubber mallet might do the trick. On the stock damper/pulley set, the gear the timing belt runs on is just held in place by the whole assembly and that big bolt.


Title: Re: About to pull head: questions.
Post by: SilverMiataRacer on August 30, 2016, 11:45:19 PM
Pay very careful attention to the position of the key in the crank nose.  It has a slight curve on one side of one end.  Pay attention to where that is positioned and make sure you put it back in the same way.  My choice is to use a new key, new crank bolt and new pulley bolts and Loctite and torque them carefully.


Title: Re: About to pull head: questions.
Post by: Ex36 on August 31, 2016, 02:54:45 AM
I have all those bolts and the key new on order from the dealer.  Boy, I discovered my problem though.  The very outer edge of my crank pulley, the part that sticks through the accessory belt drive pulleys and the trigger wheel has a ring of corrosion, which makes it effectively kind of mushroomed outward.  It took about 20 minutes of yanking on the pulleys and walking them forward to finally free them.  The trigger wheel is presenting more of a challenge since it's thin and has less substance.  Man, I should have paid a shop to do this--poor suckers would have eaten hours and hours of labor because no quote would have been high enough!


Title: Re: About to pull head: questions.
Post by: Ex36 on September 05, 2016, 03:38:41 PM
I got the head off!  2 quick questions:

1.  How clean do I need to get the bottom of the head and the top of the block?  There's lots of black residue that I worked at for awhile with parts cleaner.  Now the only way to remove what hasn't come off would be a plastic putty knife and lots of patience (I know I need to be careful not to scar up the surface).  Is that worth it or not?

2.  As I tried to remove the head, I knew I would inevitably have a thing or two still tethering it (which I did).  So, as I tried to remove it I tilted it up and put it down a couple times.  I was trying to be careful, but I probably didn't have it sitting back on the centering dowels and therefore a touch out of place.  Now that I have it off I see that the valves are pretty close to the edges of the piston walls, and they extend down pretty far depending up cam position.  How fragile are they?  I don't know that I did, but if I put weight on them are they very fragile?  I've moved the cams around and inspected all valves as they close and nothing looks amiss, but I figure a problem might not be apparent to my eye.


Title: Re: About to pull head: questions.
Post by: '95MSM on September 05, 2016, 04:01:03 PM
IMHO it would take more than the weight of the cylinder head to bend a valve IF you always set the head down softly and never leaned on it.

I don't believe it would be possible to visually spot a valve bent enough to eventually become a problem without having it out of the head. If you pull the valves out, I would lap them and examine the resulting pattern. Depending on how many miles you have on the engine, that might be a pretty good idea at this point anyway. Unfortunately, pulling the valves out is difficult (impossible??) without a special tool that allows access to the keepers while the spring is compressed.

You want the block & head to be completely clean. The pattern of the head gasket will "stain" the metals, so you'll never get it to look just-machined, but you don't want any residual material. Zip/zero/nada. FLAPS will have gasket scrapers that will work better than your plastic putty knife.


Title: Re: About to pull head: questions.
Post by: Ex36 on September 06, 2016, 07:36:53 PM
Yes, I was pretty gentle with the head--I knew it was fragile.  I had myself and my son lifting it, so we had enough muscle to be careful, and my daughter was a "spotter" looking for tethers keeping it from being freed.

I'm not too inclined to do any more disassembly (I don't feel I want to mess with cam, lifter, and valve removal).  That makes me a feel a little lazy, with the head currently sitting on my workbench and all, but I am sick of not having the car to drive (with glorious NC fall weather right around the corner) and sick of spending money on it.  My exhaust manifold gasket was a mess--clearly leaking badly for a long time at #4.  So that will be fixed and likely accounted for poor turbo power.  What remains a small mystery are my slightly bad compression and leak-down numbers for #1 and #2, which I don't have an answer for.  I couldn't tell that the head gasket was compromised in any way, but then again I also didn't put many miles on the car with it being suspect (after my two big backfires) so I wouldn't necessarily expect tell-tale signs (though I'm ignorant about such things).  I did find the coolant overflow bottle cover blown off, so it seems the coolant system got over-pressurized.

I'm close to buttoning it back up.  The dang pulley boss on the outside of the crank pulley is still giving me fits.  Patience got the harmonic balancer and trigger wheel off, but now I'm stuck with the pulley boss, toothed crank pulley behind, and Woodruff key to remove in order to complete the TB service.  They're stuck and I'm frustrated!


Title: Re: About to pull head: questions.
Post by: mr_hyde on September 08, 2016, 02:02:02 AM
If you are curious about your valve seats, you an put the head upside down and rotate the cams so the valves in #1 are closed all the way.  Drop a few tablespoons of gas in the bowl and see if it leaks out.  Repeat for each cylinder.  If you find one that runs right out like an open drain, it would be worth having a shop lap the suspect valves at least.  It would be a shame to reassemble a 'problem' with as far as you have it apart.


Title: Re: About to pull head: questions.
Post by: '95MSM on September 08, 2016, 04:26:37 AM
^ Good suggestion.


Title: Re: About to pull head: questions.
Post by: Ex36 on September 08, 2016, 05:38:08 PM
Thanks for the suggestion--I had heard of such an approach, perhaps with carb cleaner (probably same difference).  I haven't looked at what's involved other than to know I'll have to plug the spark plug hole.  I'm not sure if the plugs are short enough that I can insert by hand on the top side and flip the head over without it hitting the workbench?  Also, do you know what size wrench goes on the cams?  I tried an adjustable and it's so bulky it's too easy to catch the sides of the head when the valve springs suddenly rotate the camshaft.


Title: Re: About to pull head: questions.
Post by: '95MSM on September 08, 2016, 09:02:54 PM
I've always used adjustable (Crescent-style) wrenches. Just make sure they fit the raised section on the camshaft well.

Which has prompted me to wonder if anyone is applying the wrenches to the actual lobes. Don't do that - there is a raised boss cast into the shaft of the camshaft. Put the wrenches there.


Title: Re: About to pull head: questions.
Post by: mr_hyde on September 09, 2016, 02:08:50 AM
I've always used a crescent wrench (generic equivalent).  Just be careful as the springs push the cam to the resting position.  Generally, all you hit is the end of the galley casting anyway.


Title: Re: About to pull head: questions.
Post by: Ex36 on September 19, 2016, 01:39:56 PM
I finally got the crank pulley off--wow!  I had to make a special tool to extract it (customizing a cheap 2-jaw puller ) and it let loose with a pop.  At this point I have 2 questions:

1.  Any recommendation about what to use to clean the light corrosion (that was fusing the crank pulley to the crank) off the crank nose?  Anything I should apply as I reassemble to try to make this job easier in the future?

2.  I tested my valves by filling the top of each combustion chamber with carb + choke cleaner.  It loosened up a fair amount of the carbon build-up.  And I also used this to wipe the tops of the pistons.  But I haven't been very aggressive about it and there's still a good bit left.  Should I leave "as is" or work harder at it?


Title: Re: About to pull head: questions.
Post by: '95MSM on September 19, 2016, 04:13:07 PM
If your cleaner is working decently, try to clean all of the deposits off - hot spots in the deposits can cause detonation. The downside of cleaning is that a scratch in the piston can also promote detonation, so if you are scraping, proceed with caution.

I seem to recall that Mopar sells a particularly good combustion chamber cleaner intended to be used without any dis-assembly.


Title: Re: About to pull head: questions.
Post by: Ex36 on September 20, 2016, 02:59:49 PM
I spent a good while in the garage last night cleaning, with very good results.  I soaked some old gym socks in Berryman's Chem Dip and let them soak against the carbon.  Then I used the spray carb cleaner (which smelled simply like aerosol acetone) and a plastic putty knife to get it all off.  The only failure was between the exhaust valves.

And...I don't know why since my earliest posts images no longer work for me.  :-(

(http://www.mazda-speed.com/albums/album729/IMG_0604.jpg)



(http://www.mazda-speed.com/albums/album729/IMG_0607.jpg)


Fixed linked image syntax


Title: Re: About to pull head: questions.
Post by: sfcarbone on September 21, 2016, 02:14:40 AM
On the crank pulley I have used semichrome polish to remove the light rust.  It is a light abrasive and does a good job without scratching the surface.  If you have anything that can't be polished out or that a fingernail would feel, then think carefully about assembling the old pieces back together.


Title: Re: About to pull head: questions.
Post by: Ex36 on September 21, 2016, 01:43:30 PM
I already got some Evapo-rust at the FLAPS to work on the crank nose; I agree, I don't plan on reassembling it without corrosion remediation.

I watched a youtube video of head gasket repair.  When they replaced the head bolts, they used some sealant on the bolts since they go through the cooling galleys (seems weird to me)?  Ours seem to as well, but Keith's book doesn't discuss putting anything on the head bolt threads.  Should I just install them dry, without anything on the threads?


Title: Re: About to pull head: questions.
Post by: '95MSM on September 21, 2016, 03:36:53 PM
The bolts are isolated from any oil or water passages. Clean the threads well and assemble more or less dry.

If you use a thread lube, you should torque to a higher target.


Title: Re: About to pull head: questions.
Post by: Ex36 on September 22, 2016, 12:10:41 PM
Okay, no lube on head bolts.

How resilient are the camshaft oil seals?  I oiled a new one up last night and was sliding it on by hand.  The inner, flexible surface next the shaft inverted and turned inside out over a short portion of its circumference.  I used a rounded flat bladed screwdriver (created with a grinder for another application) to push it back into place and it seemed to seat fine using a 36mm socket to whack it into place.  But I'd tear it out and replace it now if you think it's a problem rather than dig it out later.


Title: Re: About to pull head: questions.
Post by: mr_hyde on September 23, 2016, 07:14:06 AM
If it didn't tear or 'kink' I suspect it will be fine.


Title: Re: About to pull head: questions.
Post by: dbrig350 on September 25, 2016, 02:31:09 PM
I have to disagree with 95MSM, every torque spec I'm aware of assumes clean threads and a drop of oil or other specified lube on the threads of the bolt and under the head of the nut/bolt.  With thread lube you will have less friction so it would be less torque lubed vs. dry.

Dave


Title: Re: About to pull head: questions.
Post by: '95MSM on September 25, 2016, 03:47:49 PM
Thanks for catching my error. Lower is correct - I didn't go back to my notes when I answered.  :'(


Title: Re: About to pull head: questions.
Post by: Ex36 on September 26, 2016, 02:14:07 PM
Okay, so I should put a little oil on the threads and then torque to 58 ft.-lbs. in a couple increments, following the correct pattern?

I got the head gasket on, although the head is just sitting in place with two bolts hand tight to keep it from walking.  One question: I compared the new and old head gaskets and they're the same pattern and oriented the same, so I'm confident they're correct.  Why is is that some of the holes in the block, particularly on the front passenger side, get covered up by the gasket?


Title: Re: About to pull head: questions.
Post by: SilverMiataRacer on September 26, 2016, 03:19:20 PM
That's the change of water flow that has been discussed in using the Reroute kit with the standard MSM head and gasket.  You might be closing up holes in the block because the head doesn't actually have those passages in it.


Title: Re: About to pull head: questions.
Post by: Ex36 on September 26, 2016, 05:11:08 PM
Looking at pics of my head and the block, there are many passages/holes that both have in common that aren't allowed to communicate because of the head gasket, which has many fewer holes in it.

I looked at the Jim Ellis website to look up the Mazda part number for head gaskets for an '05 with turbo and without, as well as '99.  All have the same part number, so it looks like there's a single gasket for all those engines?  I expected something different between the '05 non-turbo and the '99, but no.


Title: Re: About to pull head: questions.
Post by: '95MSM on September 26, 2016, 05:34:58 PM
Manufacturers will go back and update replacement part part numbers on prior model years when they develop an improved part. Of course they might also do that if the new part just works "okay" on prior models just to save money.

I think it was Navistar (class 8 trucks) that put the annual cost of maintaining an sku (stock keeping unit) at over $15,000 annually, and that was years ago on presumably a smaller parts and service system than Mazda.