TheSamba.com :: View topic

Thu Feb 24, 2011 4:12 pm

BEN,
Thanks for the advice, and you are correct in that I cannot yet do a compression test - waiting on a bell housing. You are right also about it being fun.

Dylan,
Thanks also, and I did call Mike at RMW this morning and put an engine hanger and exhaust on order.

Thu Feb 24, 2011 5:14 pm

With the cam covers and end caps off one can take a first look inside at the cams themselves, and they do look great.

First step in getting the cams out is to line them up for removal. Both cams have a hex section for fitting a wrench, then turn until the two end notches are set - both down for the left side and both up for the right.

You can then look on the inside of the gears and see the matching punch marks are correct.

This kind of detail was a very pleasant surprise for me. Notice that the cam is identified in the casting as left-side intake. Also, to the left, that cam cap holder is identified as number two cylinder intake. Nice isn't it?

The Subaru manual makes a big fuss about the need for keeping the cams parallel to their seats when removing them, and here is the reason. This is the thrust faces for this particular cam, and they are precise. They must be easy to damage, for great emphasis is placed upon using utmost care.
The intake gears are made up of two sections, and they are spring loaded. That 6mm bolt in the photo is temporary, and is there to prevent spring action while the cam is being removed.

The lifters must be organized and eventually go back into the same hole they came from. They have a nice waist groove which makes for a handy fit into cardboard sheet cut with 1 1/4 inch holes.
The cam caps are critical items also, and deserve great care. If one is damaged the entire head must be replaced.

Thu Feb 24, 2011 6:38 pm

Keep this up and I will have to send you all my spare EG33s for rebuilds.

Love the photos.

Nice job!

=D> =D> =D> =D>

Fri Feb 25, 2011 3:52 pm

Decided to stop here and run tests on the cams and the parts of the heads which support them. Better to find out now if there is a problem. They all look so good, like new really, that it seems doubtful there could be a problem. Still, better be certain.

This is one of the intake cams, and clearly shows the actual fixed gear is only about 2/3 of the thickness. The other third is made up of that little movable gear, which I noted earlier is spring loaded. Subaru calls it the sub-gear.

Anyone who has ever turned a loaded camshaft by hand knows very well what an uneven load it is. Turning the shaft compresses the valve springs and takes quite a force. Then as the lobe goes past it highest point, the expanding spring acts to actually spin the shaft forward. And, this uneven action is taking place, in each revolution, with all the valve springs on that cam, resulting in a very jerky load indeed. This is why Subaru designed in the sub-gear.

The little sub-gear is spring loaded to keep the teeth of the driving and the driven gear engaged throughout this ever changing load-cycle. In effect it acts to eliminate the backlash between the cam gears and thus reduce noise and wear. I believe it is elegant in its simplicity.

To conduct backlash testing of the gears sets, the sub-gear must be first be removed from both intake cams. Also the spring inside the little gears is a question mark until we take them out and measure.

So, turning the sub-gear clockwise will compress the spring and unload that 6m bolt I placed in earlier. It can then be taken out with only finger pressure, and all the spring pressure released.

With the spring relaxed, the rather large snap-ring on the left comes off, and with it the washer and the sub-gear. Then the spring is lifted out. It is tested for further service by measuring the gap shown with the pointer.

The two sub-gear springs on this particular engine measured:
Left cam - 27 mm and right cam - 27.1 mm. The specified gap is 24.88-28.88 so I am good to go.

So next I checked all four cams for run-out. I didn't expect any of them to be bent, and wasn't surprised to see that dial gage wiggle a little, but too little to even read.

Then I moved on to measuring all the journals and cam lobe heights. They were pleasingly similar and I will only give the average (they were essentially all the same). Number one journals were 1.2583 in. Number 2,3 and 4 journals were 1.108 in. Those numbers are at the high end of the standard for new cams.

The lobe heights were 1.541 in. on the intakes and 1.571 on exhausts.

Good as new!

The lifters are already out, so I can now set the cams carefully back in place and measure the thrust clearance for each shaft. It turns out to be incredibly small.
right intake .0008 in
left intake .001
right exhaust .0005
left exhaust .0005

Again, these numbers are at the low end for a new engine. Incredible to me.

Now I can put both cams in and see what the backlash is on the set of gears. Remember the sub-gear is still off the intakes.

On both sides, the gear backlash measured out at 0.004 in. Standard for a new engine is 0.0011-0.0069. So we are right in the middle of the range for new gear sets.

My last testing was to check the oil clearance inside the camshaft bearing caps. We already know that the shafts are at new spec. but nothing says the bearings aren't worn, and excessive oil clearance here means new heads - there is no other remedy. So lets check them with the old standard method.

That is .051 on the millimeter scale, and every one of them checked the same. Standard oil clearance here for a new engine is 0.037-0.072
so again we are right mid-range for a new engine.

This has been a happy day, and certainly I am encouraged to now dig in deeper.

Fri Feb 25, 2011 9:02 pm

Today, this packet arrived. Welcome it is for it was a test order, containing many obscure vacuum hose sections which I worried would be largely NLA. It is very encouraging that every item on the list was filled.

Included is the EGR solenoid valve, and yup, I tested it for sure. It opens and closes just about 2.5 vdc.

Sat Feb 26, 2011 2:55 pm

Took the heads off today, and was surprised to find this buildup of coolant inside the water passages.

And it was present in the engine passages too. Here on the bottom side of the engine it was as much as 3/16 inch thick. Might we expect to find the same buildup inside the radiator? Can anyone identify this by its color? I think it might be DEXCOOL.

Inside the cylinder bores all looks OK to my eye.

I believe these are the factory gaskets, and they appear to have gone in dry - without any sealant of any kind.

Just a little light cleaning with toothbrush and lacquer thinner. I looked closely for cracks. Didn't see any.

And the engine now is reduced to a size that looks like it might go into a Vanagon.

Sun Feb 27, 2011 3:14 pm

UGH, Now that is another ugly sight! But wait....

Here inside the water pump is even worse. Is there no end to this anti-freeze sludge? I knew it was going to look bad, for I couldn't turn the belt wheel. It is right and truly frozen up.

Sun Feb 27, 2011 3:22 pm

That is looking like a chemical sealant used to extend the life of head gaskets.....not just sludge.
it appears that it was applied a few times.
Just my experience.
Double check the head gasket mating surfaces!

dylan

Sun Feb 27, 2011 3:31 pm

Inside the block is no better. What would you say? Almost half blocked up with the stuff? Sure wish I knew what brand it was, so I could stay well away from it.

No surprises here. The oil pump looks like a quality item. in fact, I have marked it for testing and will probably put it back in service if it passes.

This was sort of interesting. Subaru calls this the oil separator cover (and claim it removes oil mist from the blow-by gasses). I remember reading somewhere that the early engines had plastic ones, and it was recommended they be replaced with metal. I do think that was done on this engine, and I noticed the sealant used was black, while all the factory stuff I have seen is grey.

Those little screws were reluctant to back out. That is a snap-on number four screwdriver which failed in the effort. Finally had to resort to an impact driver, which hasn't been used for years.

Sun Feb 27, 2011 3:38 pm

Thanks Dylan and I seem to remember something vaguely now, about a head leakage problem on some of the Legacy engines. Subaru offered some chemical sealant for owners to use as the remedy. I bet you are exactly right on that.

Sun Feb 27, 2011 3:43 pm

I have seen the orange goop on most Subaru motors over 150k miles.
Not sure which brand it is, but Bars HD is purpleish.
Getting it off all the interior walss of the motor is a task.
I remove it because i don't want to chunk to break off and clog passage ways or get lodged in the thermostat.

dylan

Sun Feb 27, 2011 3:52 pm

Yes. I will certainly try to get all of it out that I am able to.

Sun Feb 27, 2011 4:52 pm

JWPATE wrote:

Inside the block is no better. What would you say? Almost half blocked up with the stuff? Sure wish I knew what brand it was, so I could stay well away from it.

No surprises here. The oil pump looks like a quality item.

This was sort of interesting. Subaru calls this the oil separator cover (and claim it removes oil mist from the blow-by gasses). I remember reading somewhere that the early engines had plastic ones, and it was recommended they be replaced with metal. I do think that was done on this engine, and I noticed the sealant used was black, while all the factory stuff I have seen is grey.

Those little screws were reluctant to back out. That is a snap-on number four screwdriver which failed in the effort. Finally had to resort to an impact driver, which hasn't been used for years. I hope the screw driver was not one of those snap-on older plastic handed jobbers that they do not make any more.

Sun Feb 27, 2011 4:59 pm

Alaric,
Actually this is the second time I have had a Number 4 fail. Last was probably five years ago, and the guy on a snap-on truck knocked the handle off and hammered in a new shaft. We shall see.

Sun Feb 27, 2011 9:26 pm

Excellent posts and pics. I believe its recommended to Locktite those five 6x14 cover screws that are visible in your picture of the oil pump.

Mon Feb 28, 2011 9:12 am

Thanks Kenmag - Yea, you sure wouldn't want them to loosen and back out. The '92 service manual doesn't specify anything on those screw threads, but I think blue locktite would make sense.

Mon Feb 28, 2011 2:53 pm

Back with the oil pump here. And, yes, those five screws didn't want to come out either, but no broken screwdriver this time.

Subaru instructs us to scribe the two rotors so that they can be returned to their original positions after disassembly. But I don't get it. Notice that the outer rotor has one more tooth than the inner. The inner is the driven gear, and as it rotates the outer does walk around it. In other words, the set of rotors are constantly changing position when the pump is operating. A scribe mark would seem foolish to this poor peasant. Furthermore, there already are two punch marks near the end of that pointer in the photo. They were far apart when I took off the cover, but rotating the pump a few revolutions brought them together as seen, and illustrates the point made above. I didn't scribe anything.

In order for the outer rotor to walk around as described above, the open side of the gear set must clear each other, but oh, not by much. Here I am testing the tip clearance, and was able to get the .05 mm blade in there - but not the .1 mm. So the clearance on this set is between .05 and .1 mm with the new pump standard being .04-.14.

So far so good.

The new pump clearance standard between outer rotor and case is 0.1-0.175 mm. This pump is at 0.15 mm so still in the new pump range.

Here I try to fit the .05 mm blade between the inner rotor and the cover. It will not go, and it is the thinnest I have. New pump standard is 0.02-0.07. Again we are in range for a new pump.

To check how far the outer rotor is below the pump body, I chose to use a dial gauge. Set it at zero on the pump body, and with a few mm of preload - then move it over to the outer rotor. It reads just under .05 mm, say, .048. The new pump standard is the same as the above test of the inner rotor.

So what's not to like about this oil pump? It is completely in spec. for a new unit.

With that in mind, I press out the old oil seal now, while it is easy to do.

Thu Mar 10, 2011 4:12 pm

With the help of that Subaru slide hammer, I took out the piston pins today in anticipation of opening the case.

This sight did not look encouraging though. The case bolts are down hidden under that orange muck, and they look very corroded indeed. They are twelve point bolts, so it doesn't take too much imagination to expect there may be problems ahead.

There was. Of the 12 bolts inside the water chambers I was only to get nine of them out. Three just stripped off the corroded points and ended up rounded off.

Those two on the left were outside the water jackets and the others are some of the ones I was able to get out.

About the only thing I can think to do is attempt to drill out the three remaining bolts enough to get the heads off them. I wondered about that shoulder area of the bolt shaft just under the head, so I cut the head off one and checked whether it would pass through the drillings OK. It does.

That still leaves the issue of drilling off those heads. They are down there in the muck at the bottom of the water chambers, with little room to work. It will take long drill bits, and such things do not always end well for me. If I cannot drill them out.....then this will be the end of the road.

This has me really discouraged about the future of this engine.

Thu Mar 10, 2011 5:37 pm

One last thing to try. I assume the stripped heads are still on the bolt. Get a craftsman extractor set and pound one on the stud head. They are reverse cut and will really grab when new and sharp. Put your socket on the extractor and I bet you can get them loose.

The key is to get a new set which should be razor sharp and will get right on it. You can get them started by tapping them on using the right socket and extension. I have been amazed how many times these things have saved me from untold grief.

Good Luck.

I hate to see you give up, since the thread is so well done and the photos are great.

Thu Mar 10, 2011 5:45 pm

Considering your obvious knowledge base, it might be stating the obvious, but here's my suggestion:

Use a 12 point socket one or even two sizes smaller. Grind off the tip of the socket a bit, being the slightly radiused end of the socket that otherwise enables the socket to slide easily on to the nut or bolt head. This gives the socket a sharp "cutting" edge and also allows the socket to grip more of the bolt head. You might consider heat-treating the socket tip with a torch and quenching to harden the end.

Then, line up the modified socket as best you can with the ruined points on the 12-point bolt head, and then drive the socket on with your extension. Then use an impact gun or impact ratchet to persuade the bolt to budge. Repeat if successful.

Based on your dilemma, I now know I am not going to split the case on my SVX engine when I re-seal it.

Best of luck.