yeah it looks like you could see daylight through that gap. I suspect the lip folded over

Trying to remember, maybe it was the OEM seal that came with the plastic sleeve. Since I have the tool I have only used it but when I did assemble the motor I put the RMS in adapter plate first then mounted plate seal onto crank/motor just using oil and a "twist" motion when I did it. With pan on & motor in car I have used the tool

put oil or grease on crank also when you install the new seal

 

Will do. I have another seal ready to go. I figure, I will also measure the distance from the inside wall of the RMS housing to the crank at the top, left, bottom and right, maybe even the diagonals. If everything is equal there, then I screwed something up with the seal. If not, time to find a machine shop.

 

I thought I had a micrometer, but was wrong (that is added my list of wants). I found that my 6mm deep socket fit pretty well inside the gap between the RMS housing and the crank. As feared, there was plenty of room on the bottom and right side to run the socket back and forth. As soon as I start to make the curve towards the top, the socket got stuck. The same story for going towards the left side from the bottom. Instead of prepping to pull the engine, I though maybe the RMS housing is out of round, so I lowered the oil pan, cut the rear part of the pan gasket off, and removed the RMS housing. I saw no distortion of the seal, and everything appeared to okay. Measurements across the housing seem to be even, and the new seal went in without and distortion (2x4 method). Reinstalling in the housing was significantly less easy; I was not able to twist because of the metal centering piece on the right side. To get the seal on over the crank, I used a thin soft plastic interior removal tool that I lubed with oil, sliding into the seal, to get the rear lip over the crank. From there, I hand threaded the 3 bolts and one nut allowing the seal to sit and centered as possible, finally tightening down the housing. It is better, but the outter lip of the seal is still slightly off. There is also a tiny gap on the left side where the seal pushed up slightly.


Top seal

Right side seal

Bottom and left side seal

Left side RMS housing, small gap below housing where the block can be seen

Right side RMS housing

From what I can tell, the inner lip of the seal with the spring is tightly seated around the crank, where the small gap is the outer lip. While allowing the seal to set the position of the RMS housing, the gap to the left and bottom are much closer to the top and right side. I have three questions from here:
1. Does this look okay? I am confident that the inner seal is okay, I am really only concerned about the outer lip of the seal.
2. While reinstalling the housing, I got a fingertip worth of oil on the housing seal on the left side near the stud. I think I should pull this off and install with a new gasket, thoughts?
3. With allowing the seal to place the housing, is the small gap on the left side huge deal for the oil pan gasket? Could I just extend the corner RTV a little more towards the stud to compensate?

 

You put a new RMS adapter to block gasket on, right?

Not quite following your ? but if I understand the seal around crank is not good (even) around crank, right?

If so, and this is weird, that suggests the crank is not centered in the block but the old RMS did not have the appearance of being off like your, now 2 new seals, had appeared, right?

On the gap between pan and block since you cut the rear of the pan gasket out are you sure one of the metal spacers that is imbedded in the pan gasket did not remain on the rear stud from block which then would space the pan gasket away (had this happen before)?

Are you intending on putting the old cut out portion of pan gasket back in or replacing the entire pan gasket?

Your situation is odd to say the least but given you can clearly see gap on some portion of the RMS mating to crank unevenly....something not right

"Maybe" the crank (line bore) was off just ever so slightly which is the cause of your initial RMS leak. If that is the case you have a significant issue that means the motor has to come out and completely torn down to confirm the crank caps/line bore are in fact true. That would beyond suck so confirming the why without doing that is where you are at now and I am not seeing a 3rd RMS install would resolve this. Putting RTV around the outer edge of RMS would be OK to "fill" gap if the gap was between outer edge of RMS and block but your issue is inner seal lip and crank...which RTV if of no use on a revolving crank to seal surface.

Maybe someone with their eyes can advise next step different than my thoughts....but your situation is certainly weird as, especially with the "tool" this should have been a plug & play seal swap.

EDIT: still scratching my head about this as the root cause thought is a major engine redo....so is it worth just buttoning it all up and starting the motor with no trans (just FW) to see if it pisses oil. Obviously if it does not that is a major + and "maybe" the seal self "centers" once crank starts turning...IDK. Just trying not to be doom & gloom thoughts or over analyzing pics on internet

Fred (Injuneer), if you are reading this, your thoughts??

 

Thanks, I was full of doom when I tore into it yesterday. When I figured out the the distance between all of the sides of the housing were off, I was ready to pull the engine, then figured I would throw the hail Mary and pull off the housing.

For question 2, I did remove all of the previous gasket between the block and the RMS housing. When reinstalling the housing however, since the crank and the seal were coated in oil, I got a fingerprint size touch of oil on the new gasket. Before I put everything back together, since the gasket was a dry installed, I wanted to verify if that touch of oil was a big deal (I am feeling like I should just replace it.

For question 1, there are 2 lips on the RMS, the inner lip with the spring is solid around the crank. It is the outer lip that has a tiny amount of gap. For how the seal was before, I didn't take reference pictures before hand, because I didn't realize there was an alignment issue. When looking for a leak though, I recall seeing a drop of oil between the bottom of the crank and the seal, and don't think I could have if the gap was not there. When allowing the seal to position the RMS housing, on the left side where the RMS housing stud goes, there is now a small gap, with the RMS was pushed up slightly. In pic 3, you can see that the bottom of the RMS housing is not flush with the bottom of the block.

My feeling is that the line bore is not perfectly straight, which lead to this issue. Strange all the way around though, because if the crank was off, I would have expected issued getting the transmission in.

 

The gasket between RMS adapter and block is just a regular gasket. a finger print of oil on it IMHO should not matter. I prefer to put a "skim coat" (read VERY thin coat) of RTV on those kind of gaskets. There is a PTFE RMS that does install "dry" but the housing gasket is just a regular paper/fiber type so a fingerprint of oil is not a problem on those

While the inner, spring wrapped, seal lip appears to be uniform on the crank (not sure how you would see that though) the rear seal lip clearly is not which to me says WTF, this is not right unless somehow on any of your install methods you are inadvertently distorting the seal....but I would think the seal would settle in flush all the way around but somehow is now distorted...or your line bore on the crank is off. Yeah your note about the tranny input shaft not lining up would be a problem and if there was enough "slop" to get it in than the pilot and input shaft tip would show signs of wear as that would be the mating point of off alignment crank. If you never had driveline vibe from this motor I think that is not the case...but then again we "see" a gap.

But now that the RMS has been removed and RMS adapter installed and now the adapter does not seem to line up right (suggesting something wonky with crank alignment) I would remove it, pull the RMS and re-install the adapter, new gasket with skim coat of RTV, put pan and new gasket on using RTV (I prefer Permatex Black "ultra" as it is best for oil) then install a new RMS using your tool

Then put FW on and start motor and see if it leaks. On paper with the seal gap I suspect it would but maybe we are just over analyzing this, IDK.....or maybe "3rd time is a charm" for the RMS

I say this because the other alternative is pull motor and completely tear it down and have a machine shop go through the block and line bore which is beyond a massive job that just started as "hey I have a small RMS (or what appeared to be RMS) leak. So suggesting just put new seal/gaskets in and try running motor without trans to see if in fact it still leaks even with a gap of the RMS

another note is I have never had any problem with any Felpro gasket or seal. You could, if you feel the Felpros for whatever reason are not happy with your motor, go to the dealership and buy a OEM one. They are not much $. Just spit balling other possibilities

 

I cannot imagine that the RMS would be any different if I did it a third time, since the alignment seems to want to do the same thing using two different installation methods. I also don't think it is the Felpro. Remember that taking a 6mm socket with the tip pushed flat against the bottom lip of the RMS housing was tighter on the top and left than bottom and right. When I had the housing unbolted, I did the same test with the socket, and in its current position, was able to get the socket to roll all the way around the crank (it was getting stuck on the left/top when testing originally). How do you bypass the clutch safety swith to get it to start without the tranny? Is there anything else you need to do with the wiring harness?

 

you could just zip tie the NSS closed. I have a B body with a T56 using a F body NSS on my custom made clutch pedal assembly so assume it is the same as yours.

You don't want to push clutch pedal with hydraulics attached to it so zip tie or something to close the switch or cut and splice the 2 wires together but you likely don't want to cut then re-connect them just for this start to see if the RMS leaks

Given the engine is just supported by MM I would, assume you have this already, have a floor jack or jack stand supporting engine also under pan. If the RMS leaks you should see quickly either seeing oil come out or when you pull FW to see if RMS is "weeping" oil

 

*update*

I ended up getting a rubber Cometic RMS and testing pulling the pin out of the block. I pulled the housing off, removed the pin, then let the fuel pro gasket center the housing. It looked way better, so I replaced the rear gasket, then torqued down the housing. I then removed the RMS and installed the Cometic with the tool. It is still a little off, but nothing like it was.

I also picked up a set of ARP bolts for the oil pan, and what a difference with the 12 point heads, washers and bolts to replace the studs.

I had bought a replacement clutch master cylinder, so I just pulled the CMC and tied up the wires to start the car and look for leaks.

I am not seeing anything out of the RMS, but am getting drips off the back of the intake manifold. I had pulled this off after finding the issue with dye, but didn’t see anything after, but obviously screwed something up. I have new gaskets ordered and hope to get to it next weekend.

Stupid oil leaks!!

 

Sounds promising Drew on the RMS. On the intake gasket I prefer the FelPro "printo" series. They have the blue sealant bead around the ports. The china wall is prone to leaks. I prefer Permatex Black "ultra" RTV. Wipe all surfaces with acetone before install. Make sure you set the intake on dead nuts so you don't slide it once it contacts the RTV. Using 2 short pieces of wood dowel or donor bolts with the head cut off on front & rear of one side of the motor as guides works very well. Let the RTV cure overnight before starting motor

 

I am definitely crossing my fingers that this will be the end of oil leaks. When I did the intake last time, I used bolts at the front and rear with the heads chopped off to prevent forward and reverse movement of the intake when placing. Looking back at Shoeboxes site, I cannot recall if I ran the RTV all the way under the intake gaskets, and am guessing that is where my issue is. I also did not make a lower torque pass, which also could have done it. I did allow the car to sit overnight before starting it. In regard to the gaskets, I have an LT4 top end, and was not able to find Felpro gaskets that fit. I ended up needing https://www.summitracing.com/parts/nal-12367777 which is what originally came with the head/intake combo I purchased. When preping the china walls, I used brake clean rather than acetone; could that have also caused the issue?

Here are things I plan to do differently:
1. Clean head surface and china walls with acetone
2. Run RTV all the way under the intake gaskets
3. Torque the manifold to 71 in pounds on the first pass, then a second pass at 35 ft pounds

How long do you normally allow the RTV to tac-up? I want to say I gave the RTV about 5 minutes before dropping the manifold on it last go.

 

I would think brake clean would be OK but I prefer to "wipe" with clean rag (so I can see when the surface is clean when no more black is on rag) using acetone since brake kleen is a spray. Whatever you want is fine

I have never run RTV "under" the gaskets. I put those on first then run the RTV bead about 3/4"-1" up onto the gasket. I let the RTV set up about 10 min and have not had a leak.

IIRC the correct way to TQ the intake is 2 passes unless FSM says otherwise (3?)

There definitely is a "pattern" in TQ sequence basically starting center and working outward in alteration front to back & side to side

I assume you dry fit intake on and confirm it mates solid. Heads and blocks that have been decked "sometimes" require some manifold machining and or hole enlargement

I just let motor sit over night before starting it

Yeah if you have LT4 intake than different gasket

One "trick" I read about years ago on intake manifold china wall leak was to use a punch and dimple along china wall and intake so RTV had "recess" to cling to. Supposedly this worked on stubborn china wall leaks but I have never needed to do that

 

For the brake clean, I spray into a rag then wipe. If the different in chemical will not make a difference, I will just stick with what I have. I will up the RTV time to 10 minutes before attempting installation.

I was referring to this for the RTV under the gasket:

RTV up to the gasket

I am fairly certain that this was the pattern I had used to tighten it down before, but I know I did not use this image as I did not make passes at different settings.

I have not made a dry fit since everything came back from the machine shop. The heads were sent to a shop after being delivered for porting/polishing. I will add the dry fit to my list this go.

 

Sure your brake kleen/wipe method is fine.

IDK if the RTV "under" the gasket is better than over...I have just always done it over. Rob (shbox) certainly knows his stuff and is a huge asset to the LT1 community so I would think either way is fine unless Rob notes a "why" the RTV goes under. Maybe some intake gaskets don't have the little plastic posts that hold the gasket in place and RTV under it secures it better before dropping intake. The stock & Felpro gaskets have the small posts but IDK about LT4 ones

Given your heads have just been serviced, especially if decked some, than yeah a dry fit to make sure all surfaces are flush. You can use the smallest feeler gauge you have to see if it slides in anywhere it may not be flush.

Like anything else its the prep time vs install time that makes for a better end result

I assumed you did confirm any previous rear leak was not from the oil pressure sender or its fitting but now is a good time to seal those threads if that is a unknown while they are easily accessible without intake

 

The LT4 gaskets also include the tabs to keep them aligned while installing.

I am going to take a hard look at the RTV when I pull the intake off to see if anything stands out as missing. I have a pretty good idea of what should be

I don't remember if I resealed the oil pressure sender, but you're right that everything is apart, it doesn't hurt to seal it again. I believe I used the liquid Permatex thread sealer (white) the last time. Is that what you recommend?