Where to go from here?

[jauringer]

Well it started out as a bad day and has progressively gotten to the point where I want sell the Scout, melt my tools down and have them made into a set of golfclubs. At least I half way know what I'm doing on a golf course.

Keep in mind this was an incidental discovery. No bent pushrods, misses, etc. I did have two lifters make noise on me about a week ago (roughly) which is posted here. I pulled them, cleaned them out and went on my way. The only reason I even saw what I saw was because I had what looked to be a leaky rms (which I was bummed about anyway). When I got behind the engine I saw a potential leak point on the bottom of the rear cam plate as it looked like it was collecting oil before being blown around by the flexplate. Anyway, removing the rear cam plate is when it all went to hell in a hand basket. With all this damage, I just don't understand how I had the op I did? See pics below, I'm not sure it could get much worse.

Engine details: has 500 miles. 304 60 over- contoured piston engine, 8.9cr, isky split duration cam. .010/.010 crank. Roller tip rocker arms, 110-295 valve springs iirc.

History: engine break in went relatively well. I did have to shut it down at the 15min Mark when my pickup coil connection started coming loose. I stopped it immediately and then ran it for another 20 minutes afterwards. Never got below ~2000/2500 rpm. About a week ago or so. (post is here) I had two lifters start banging at start up. They took a while to pump up and bled down quickly. I pulled 4 lifters as I wasn't sure exactly which ones they were, cleaned and reinstalled. They stopped making noise. (I think I've got a pretty good idea of what clogged the up in the first place now) since then I've been driving it everyday. Hot idle is @ 24 psi and cruise is ~50-55. It's never once dropped below this.

Little bits of cam bearing behind the rear cam plate. I began tear down immediately and this was just the beginning.

The worst of it all. #3 cam bearing looks like it has actually spun.

Had to force the cam out and after I did the #3 cam bearing just fell down in the pan.

Used to be an oil hole there.

#3 bearing surface

#2 and #4 cam bearings. Majority of the damage seems to start at the 6 o'clock position. The #1 cam bearing is the only one that seemed to survive.

Cam journals:
#5: the #5 cam bearing has the exact mold of this journal in the 6 o'clock position.

#3

#2

#1 (guess I didn't shoot #4.)

The rod and main bearings look relatively well considering what they've had to endure. Thee is some embedment. Especially on the #3 main(thrust) where the cam bearing hole was blocked.

Here are a few remaining shots.

I'm at the point where I have no idea where to go from here. I know I need to take a bore gauge to the #3 cam bore and see what kind of damage I'm looking at. Most importantly I need to figure what happened, why it happened, and how not to do it again!

Any help would be greatly appreciated. The entire block is torn back down so if there are anymore pics needed, I can handle it.

Jason

 

[Scoutboy74]

Wow jason! This is the very definition of sucks ass. I have a vague idea of how much time you put into this build. I know you didn't do a rush job by any stretch. I also know you took great pains to ask plenty of pertinent questions and gather knowledge ahead of time. This seems inexplicable and yet there must be an explanation. I obviously don't have it. All I can offer you is my condolences and empathy for your present frame of mind.

 

[jauringer]

wow jason! This is the very definition of sucks ass. I have a vague idea of how much time you put into this build. I know you didn't do a rush job by any stretch. I also know you took great pains to ask plenty of pertinent questions and gather knowledge ahead of time. This seems inexplicable and yet there must be an explanation. I obviously don't have it. All I can offer you is my condolences and empathy for your present frame of mind.

Hey scoutboy, thanks man. Yes, this is the definition of suck ass for sure. I'm not even gonna touch it until I can feel some what comfortable on what the heck I did to this thing.

Fyi, I added this link to my engine build thread over on the other forum but had a comment from bill usn-1 I thought I would share the answer to here as it is important to know.

All oil holes were checked. I know 110% that every single oil hole on those cam bearings were lined up @ assembly. I even eyeballed before the block even left the machine shop and then thoroughly went through them when I got home. The #1 bearing was the only one I initially questioned and after sticking a small wire through the timing cover oiler, it was perfectly fine. Also, the cam rotated freely. There was no problem there.

However, I did not check the cam bearing clearances. My bore gauge was marring up the bearings and I didn't feel comfortable continuing. I took the cam turning freely as an indication that things were good.

I have a theory on my oil pressure reading that May or May not be right. I think any pressure I might have lost with 2,4&5 might have been masked by the fact that the oil hole became blocked on the #3? I'm thinking that might have given me a higher pressure than it really was? Lastly, on the #3 bearing. I'm curios as to why there are no heat marks or burnt oil marks anywhere around the bearing/bore area? I figured something like that would have discolored the area?

Thanks a bunch,
jason

 

[jeff campbell]

I guess about the only thing you can do now is to take it to the machine shop an have them " line bore " it to assure it's all good. At least then you'll know the bore's are a in line perfectly. Jeff

 

[Robert Kenney]

My thoughts:

never line bore or hone the cam bearings or block bores... They have to be at the oem diameter or bored up to an available bearing od oversize... I don't think they exist for the IH sv series.
The fact that they spun in the block with no visible heat witness tells me that they had insufficient press in interference with the block bores...

Another member here Jesse barton had a bearing wiping problem that I attributed to a poor cam journal finish. His complaint was a chronic lifter tick that got progressively worse as time went on. It started at 500 miles iirc. There was no bearing rotation after the damage. I recommended that he polish the cam journals to a nice finish and reinstall new bearings. He did and has been fine since as far as I know....

You need to verify some things on the block like the bearing bore diameters are to the bearing manufacturers recommendations. Each bearing has it's own location and bore id. Those id's correspond to the cams position. All 5 are different. After install the cam must spin by finger grip if installed properly oiled... I would polish the cam journals with a buffer after shoe shining with croakus cloth or 600 and finer wet dry paper.. The finish lines need to go around the journal.

You would not necessarily see a oil pressure deviation from the failure you have there.. In fact it would have been high from the blocked oil holes and subsequent reduction in oil flow..

One question I would ask you is what valve spring pressures are you running seat and open?

 

[jauringer]

my thoughts:

never line bore or hone the cam bearings or block bores... They have to be at the oem diameter or bored up to an available bearing od oversize... I don't think they exist for the IH sv series.
The fact that they spun in the block with no visible heat witness tells me that they had insufficient press in interference with the block bores...

Another member here Jesse barton had a bearing wiping problem that I attributed to a poor cam journal finish. His complaint was a chronic lifter tick that got progressively worse as time went on. It started at 500 miles iirc. There was no bearing rotation after the damage. I recommended that he polish the cam journals to a nice finish and reinstall new bearings. He did and has been fine since as far as I know....

You need to verify some things on the block like the bearing bore diameters are to the bearing manufacturers recommendations. Each bearing has it's own location and bore id. Those id's correspond to the cams position. All 5 are different. After install the cam must spin by finger grip if installed properly oiled... I would polish the cam journals with a buffer after shoe shining with croakus cloth or 600 and finer wet dry paper.. The finish lines need to go around the journal.

You would not necessarily see a oil pressure deviation from the failure you have there.. In fact it would have been high from the blocked oil holes and subsequent reduction in oil flow..

One question I would ask you is what valve spring pressures are you running seat and open?

Robert, thank you.

I did indeed find Jesse's thread and there were certainly some similarities. I never had the tick above 45mph but the events leading up to that are similar.

The non-existant heat marks had me wondering as well. I did not verify the interference fit between the bearing shells and their corresponding bores. While the engine had failed cam bearing at tear down, none had spun and I didn't even think to verify that measurement.

I also can't say the cam "spun by finger grip" it spun easily but I'm not certain it was that easy.

Op comment makes perfect sense.

Valve spring data:

110# closed
290# open

I've got a cam bearing tool on it's way and will pull the remnants and verify bore diameters. I do have another block worst case scenario.

Let me know if you need any more info. Thanks Robert.

Jason

 

[Robert Kenney]

For fitting the bearings in the event that there is any binding. A spoon or similarly shaped tool can be used to burnish the babbitt in areas of a high spot. Even slipping the cam in and turning back and forth will yield witness marks in tight areas. Burnishing or scraping is preferred in place of an abrasive device... Takes time but the babbitt being so soft, will take in the abrasive grit and you'll never remove all of it.

Look closely at the bearing bores of the block and see that the finish is factory not honed. This might indicate it has been monkeyed with.

 

[Mark Pietz]

Wow. A fresh build gone bad somehow is alarming to see! Is it possible that a wrong #3 cam bearing was installed (next smaller od) and turned? Makes me a bit paranoid knowing that on my recent build, I, too, just turned the cam by hand and detected no binding, although it seems that isn't really the best test afterall! It was, however, the original cam (reground) and just the bearings were new, so I didn't give it a second thought. I hope the cause to this disaster is found.

 

[jauringer]

Hey Mark, it's definitely alarming. I'm starting to feel a little better now that I actually have somewhere to go with this. I actually have a few extra parts too so that helps. Extra block if needed, 16 new johnson lifters, new set of cam bearings..... I just had my good Scout buddy davis come over and take a look. He's got a lot more experience than I so it was nice to have him put his hands on this stuff.

He agrees that there should be more of an indication if the bearing shell had been spinning with the cam. There's not, no heat marks, scoring, oil blockage anywhere. Somehow, even with the #3 cam oilier blocked, it was still getting oil. (maybe from the lifters above it?) the cam journal, nor the back of the bearing shell seems to indicate that it's spinning. Pics will be below you an opinion on this.

As I was walking davis out the door my cam bearing tool was at the door step. 24 hours is killer service! So I took the bearings out right afterwards.

Keep in mind that I've never installed or removed cam bearings so I have no reference. However, every single one of them came out very easy. It just seemed too easy. 3lb dead blow hammer just basically falling on the end of the tool knocked them out. I would have assumed it would have taken more.

#5

#4

You already seen #3 and #1 is the only that somewhat survived.
#2,

Here are the bores.

#5

#4

#3

#2

#1

I'm going to compare the bearing od's between the new and used set. I'll also get a measurement of all the bores. They look like factory tool marks to me though? Unfortunatly my bore gauge is no long enough to reach the #3 bore so I'll need to run that out to have done. I've got a set of snap gauges but I'm not sure I can trust them for this?

Then I'll call durabond and find out what they recommend for the interference fit so I can make a decision on what to do.

Thanks,
jason

 

[Robert Kenney]

Having driven them in before they take a good deal of force to drive in... They are a press fit and no way they should spin like yours did if the press was enough...

By looking at the old bearing od there is very little marking from being pressed in... Think you need to track down the details on the bearings used and the bore diameters...

 

[Mark Pietz]

Robert,
except for the last pic, don't those other bores look like spinnin' going on?

 

[jauringer]

having driven them in before they take a good deal of force to drive in... They are a press fit and no way they should spin like yours did if the press was enough...

By looking at the old bearing od there is very little marking from being pressed in... Think you need to track down the details on the bearings used and the bore diameters...

You got it robbert.

Robert,
except for the last pic, don't those other bores look like spinnin' going on?

Only possible spun bearing is number 3. Those bores look just as they did before the bearing went in. No way the other bearings spun and incidentally ended up perfectly placed when I pulled the engine. #'s 1,2,4,5 oil holes were still lined up before I drove them out.

I've got a msg into durabond tech. If I don't hear from "george" by noon tomorrow, I'll give them another call. I'm about to go out and see if I can figure out a way to get my bore gauge in the #3 bore.

Jason

 

[Robert Kenney]

Yeah, I got the fact that only one spun. The witness marks from pressing in and out were very faint and indicative of poor interference.

 

[Mark Pietz]

The side story is that we really trust the shops doing the work to do the right thing. So in this case it May have been bearings that didn't feel all that tight coming out, wouldn't have felt sufficiently tight going in. You'd expect the machinist to have the level of "feel" and act upon anything out of the ordinary. Another way of saying this should have been caught at that point?

Scary.

But now that you have that wonderful cam bearing tool, you can't do any worse a job than you paid "the professional" to do.

 

[jauringer]

yeah, I got the fact that only one spun. The witness marks from pressing in and out were very faint and indicative of poor interference.

Yep that wasn't intended for you, sorry for the confusion. I just wanted to make sure Mark knew that was the case as he indicated the other looked like they were spinning.

the side story is that we really trust the shops doing the work to do the right thing. So in this case it May have been bearings that didn't feel all that tight coming out, wouldn't have felt sufficiently tight going in. You'd expect the machinist to have the level of "feel" and act upon anything out of the ordinary. Another way of saying this should have been caught at that point?

Scary.

But now that you have that wonderful cam bearing tool, you can't do any worse a job than you paid "the professional" to do.

Lol Mark, that is true.however, I take all the blame for this. One of things I said in the very beginning was if it went up in flames, it was all on me. I should have measured all of this before even letting them knock those bearings in. My goal was take as much responsibility out of the hands of the machine shop as I possibly could. I verified all of their work with the exception of this fitment and that's on me for certain. As you said, I would have liked to think that if a bearing just slid in, the shop would have done something/ said something about it but it is what it is I guess. Now that I own the tool, I'll know for sure how they go in this time.

Alright, I've got all the numbers. I was able to get to all the bores last night with my bore gauge. It just took a few extra steps. Here's where I am.


Cam bearing bores

my measurements: if an oil kept me from getting to the exact x/y location, it's just offset.

1. X 2.2310
y 2.2315

2. X 2.2215
y 2.2210

3. X&y 2.2115

4. X&y 2.2015

5. X 2.1915
y 2.1910

after talking to the durabond tech a few minutes ago, they recommend .002-.0045" interference. Also, the numbers listed below are what they have specifically list for these bores which are in the middle of their range.

1. 2.2313"

2. 2.2213"

3. 2.2113"

4. 2.2013"

5. 2.1913'

as you can see, my bores are very much in spec. And it looks as though my worst nightmare has been averted! Block looks to be good!


Now, the bearings specs from durabond. All of the new bearings fall right within this range on the high side, .**5. All of the old bearing fall within this range on the low side with the exception of the #3 which actually measures only ~1/2 thousandths over the bearing bore. However, considering the dmg, I'm not sure this accurately portrays it's original od.

Durabond bearing manufactured od

1. 2.234 -.235"

2. 2.224-.225"

3. 2.214-.215"

4. 2.204-.205"

5. 2.194-.195"


lastly, I went back in and verified my numbers by locking the bore gauge in @ zero via the micrometer measurement of the new bearing od and check clearance that way. I had no less than .003" interference between the bore and bearing on any one, .0035 being the most on any one.

So, there's the data. I still don't know if I have a why for certain but I do know that I have a good block which is huge.

I need a new cam as well as a main/rod bearings so I hope to get that on order today with Jeff. I would like to have a discussion regarding my cam choice on this go around but I'll let this post simmer for a bit before I go changing the subject.

Jason

 

[jauringer]

Ok subject change. Not forever but I need to at least add this in the mix.

Camshaft! First I want to say that the isky split duration was great. It's performance is not why I'm revisiting this subject. My favorite part about the isky is the rolling 40mph punch. Dropping it in 2nd at around this range is just a blast. It pulls hard. Take off @ stop was noticeable just not as noticeable as 2nd/3rd.

So here's why I am revisiting the subject. Rpm range, compression ratio, and piston to valve clearance. (in order of importance. To me at least)

rpm range: even when I was really getting on it, I had zero desire to push it past 4000rpm. I thought I would and it gets there pretty dang easy but I just don't do it.

Compression ratio: it's less than my original goal @ 8.9 vs 9.1. It's not a huge difference but it is less.

Ptv clearance: obviously my block didn't explode so it's working. However it is at the bare min of the specs according to an article I read on engine builders association site and close to min according to my guy. With the split isky, the intake is .080" (*including valvetrain deflection*) exhaust has tons of room being right over the dish. (contoured piston) being the intake makes me feel much better and I don't want to change cams for just this reason but if there is a better combo that will help this spec, all the better. Fyi: I had originally ran the isky 1 deg retarded to get it over .100. Didn't like it though and advance the cam back to 3* advanced.

I'm looking at the timing cards for the comp 252h, isky 256, and the isky 256/262. Unfortunately the comp doesn't give me any open and closing points @ .050" lift so I can't really compare it. Between the two isky, the split duration still looks like the best choice?

Robert, what do you think?

Thanks,
jason

 

[Robert Kenney]

You only have a few choices if you are indeed not happy with the rpm range..... Remember that anything you do that will shift the power band down will reduce ultimate horse power.

1) advance the cam a few degrees more.
Will require valve pockets to be cut in the pistons.
2) change the cam to one with less duration on the intake.
3) add displacement. Tough to do but doable none the less.

I think #2 is your only real choice at this time if you must change. I personally would leave it alone.

As for the cams the comp is bigger and will make your v-p clearance tighter... The isky 252 single pattern can is the same lobe but at 112 lsa not the 110 of the dual pattern. It will give you more v-p room but will be the same as retarding the cam you already have...

 

[jauringer]

you only have a few choices if you are indeed not happy with the rpm range..... Remember that anything you do that will shift the power band down will reduce ultimate horse power.

1) advance the cam a few degrees more.
Will require valve pockets to be cut in the pistons.
2) change the cam to one with less duration on the intake.
3) add displacement. Tough to do but doable none the less.

I think #2 is your only real choice at this time if you must change. I personally would leave it alone.

As for the cams the comp is bigger and will make your v-p clearance tighter... The isky 252 single pattern can is the same lobe but at 112 lsa not the 110 of the dual pattern. It will give you more v-p room but will be the same as retarding the cam you already have...

That all makes sense and I am more than happy to leave it alone. It was more to cover my basis than anything. I wasn't sure about the comp but your comments on the other isky is what I figured after looking at the numbers....thanks for the help Robert. I'll stick with the isky split duration.

Thanks,
jason

 

[jauringer]

Ok, cams on order. Cam/rod/main bearings, lifters, rear main sleeve, and engine gasket kit are in my possession. I've got a national rms on the way.

I've found a machine shop with the ability to micro-polish the cam journals. They did my crank while I waited this morning and it looks better than it did before I put it in last time. The cam bearing bits didn't look to really do much if anything to the crank but better safe that sorry and the procedure removes very little material. Operator stated 1 ten-thousandths.


This weekend the block, heads, and crank will all be cleaned, oiled, wrapped, and put away until I'm ready for them.



Jason

 

[Mark Pietz]

Jason,
in a p.m. We talked about oil pressure. Out of curiosity I just ran mine:

10-30 break-in oil, cold start, fast idle: 50 lbs. Revving it increases it to a cut-off point of 55 lbs. That's got to be the by-pass opening. Idle: 40 lbs.

After warming up, around 2,500 rpm: 40-45 lbs. Idle: 25 lbs. I'll have to wait for driving it around on a hot day to see what worst-case numbers are, but I think they'll be fine. I checked my "build sheet". Using plastigauge, my main bearing clearances ended up at 0.0025", con rods 0.0015" (one) and 0.002" (the other three). Shop recommended crank in specs and just to polish, so their advice was spot-on. If your journals were similar, and you polish and get new bearings, you'll have dodged a big bullet in not having to re-grind.