Crankcase pressure, friend or foe? How much is too much?

[lenmann]

I was lagging a bit here with updates, hoping to have some pics of it back on the water and a big smile on my face. It hasn't quite worked out that way.

The boat is good, resting comfortably in the shop while I catch up on some odds and ends post build.

The trailer prop guard wasn't deep enough to clear the rudder so I lowered it 3/4 of an inch. My original plan was a trip to Parker/Havi to have Adrenaline fix it but there's no point in dragging a motorless boat that far for something I can do here in half the time it takes to drive there and back. Still need to paint it. I picked up the color matched paint yesterday so maybe today.

I glassed up a center floor section to cover the v-drive and driveline so my wife can get around in the boat next summer. Also built a rear seat base in anticipation of having the interior done this winter. Not sure why I don't have pics of the finished product.

The motor is on its third chapter of "2 more weeks" to have it back together. It has taken longer than expected to get pistons and to have the turbos refurbed. Key people in the process took summer vacations which I cant really be mad about, hell, I'm on vacation all the time. I stopped by the engine shop last Friday and all the parts are there ready for re-assembly now. The good news is the block didn't need to be bored, a light hone was all that was needed, and all the other internals all look like new.

Final determination on root cause looks to be a miscommunication on ignition timing and poor execution. My hand written notes from when I picked up the motor indicate that the distributor's mechanical advance was locked out. It wasn't. When I set the initial timing at 30 degrees it was way advanced and at RPM was seeing north of 58 degrees. This isn't the first motor I've set the timing on and my normal process is to set the initial at idle and run the motor up in RPM to check the total. Evidently I didn't do that. Maybe I got fixated on the locked distributor note, damn if I know. My mistake. Cost me a summer and some coin.

Anyway, off-road season starts for us next week with a trip to the Grand Canyon and the Bar 10 ranch. Motor guy plans to have the assembly and dyno runs done in... wait for it... 2 weeks or so. With any luck I will pick it up in late October when we get back and have it in the boat and off to upholstery before the holidays.

The road goes on forever and the party never ends!

 

[mattyc]

I was lagging a bit here with updates, hoping to have some pics of it back on the water and a big smile on my face. It hasn't quite worked out that way.

The boat is good, resting comfortably in the shop while I catch up on some odds and ends post build.

View attachment 1282860

The trailer prop guard wasn't deep enough to clear the rudder so I lowered it 3/4 of an inch. My original plan was a trip to Parker/Havi to have Adrenaline fix it but there's no point in dragging a motorless boat that far for something I can do here in half the time it takes to drive there and back. Still need to paint it. I picked up the color matched paint yesterday so maybe today.

View attachment 1282875

I glassed up a center floor section to cover the v-drive and driveline so my wife can get around in the boat next summer. Also built a rear seat base in anticipation of having the interior done this winter. Not sure why I don't have pics of the finished product.

View attachment 1282866 View attachment 1282865 View attachment 1282864

The motor is on its third chapter of "2 more weeks" to have it back together. It has taken longer than expected to get pistons and to have the turbos refurbed. Key people in the process took summer vacations which I cant really be mad about, hell, I'm on vacation all the time. I stopped by the engine shop last Friday and all the parts are there ready for re-assembly now. The good news is the block didn't need to be bored, a light hone was all that was needed, and all the other internals all look like new.

Final determination on root cause looks to be a miscommunication on ignition timing and poor execution. My hand written notes from when I picked up the motor indicate that the distributor's mechanical advance was locked out. It wasn't. When I set the initial timing at 30 degrees it was way advanced and at RPM was seeing north of 58 degrees. This isn't the first motor I've set the timing on and my normal process is to set the initial at idle and run the motor up in RPM to check the total. Evidently I didn't do that. Maybe I got fixated on the locked distributor note, damn if I know. My mistake. Cost me a summer and some coin.

Anyway, off-road season starts for us next week with a trip to the Grand Canyon and the Bar 10 ranch. Motor guy plans to have the assembly and dyno runs done in... wait for it... 2 weeks or so. With any luck I will pick it up in late October when we get back and have it in the boat and off to upholstery before the holidays.

The road goes on forever and the party never ends!

Damn, I've been checking in almost daily hoping for an update on this!

Glad to hear things are moving forward. I did something similar a long time ago on the very first motor I did, set base timing and never looked at advance, oops, lesson learned.

Kind of a shame to cover up all that pretty hardware, but your liner does look bitchen! Do you plan on doing any color or pins to match the floors in the boat?

 

[lenmann]

Damn, I've been checking in almost daily hoping for an update on this!

Glad to hear things are moving forward. I did something similar a long time ago on the very first motor I did, set base timing and never looked at advance, oops, lesson learned.

Kind of a shame to cover up all that pretty hardware, but your liner does look bitchen! Do you plan on doing any color or pins to match the floors in the boat?

I sprayed the driveline cover in gray gelcoat. It gets a snap on carpet piece on top. I hate to cover up the bling but it's really not very practical climbing around all that stuff, at least not for this old man.

 

[mattyc]

I sprayed the driveline cover in gray gelcoat. It gets a snap on carpet piece on top. I hate to cover up the bling but it's really not very practical climbing around all that stuff, at least not for this old man. View attachment 1282971 View attachment 1282972 View attachment 1282973

Cant say I blame you. Looks great. T nuts in the seat base I spy a ski pole in there too

 

[ChrisV]

That “2weeks” runs deep in the motor building industry. Live and learn. Thank you for posting. I always geek out when you do.

 

[ChrisV]

Hey Len, hows the build coming?

 

[lenmann]

Hey Len, hows the build coming?

Motor rebuild is complete, I got it back right before thanksgiving. The good news is, aside from trashing the pistons, most of the motor was undamaged and as new. I elected to do a full refresh; new pistons, block hone, bearings, valve job with new intake and exhaust valves. I had Carson freshen up and reseal the turbos. I took the advice given here using my fuel delivery system for the new dyno runs. Also made sure A/FR and exhaust temp were recorded as part of the process through the full range of throttle openings and rpm. It ran great on the dyno and it's back in the boat.

The root cause of the "too much crankcase pressure" problem was simply ignition timing. My notes from when I picked up the motor back in 2017 indicated that the distributor was locked out and the timing should be set to 30 degrees. That's what I did after pulling the dizzy and priming the oil system when I finally started up the motor for the first time in 2022. As it turns out the distributor was not locked out and the motor was seeing way too much timing. Now, this isn't the first motor I have set the timing on and I definitely know to run up the rpm to confirm total advance but I guess I didn't do that in this case otherwise I could have avoided the "lost summer of '23". Maybe target fixation on 30 degrees? Maybe too much excitement to have the damn thing running after so much time and work? Hell, it sounded so nice running on the hose I couldn't walk right for most of the rest of the day so that's a possibility. Damn if I know, but setting the timing correctly is my responsibility and I have learned (re-learned?) this lesson the hard way.

The weather up here has turned below sweat shirt boating temps so it will be spring before I get her wet again.

Any recommendations on a A/F meter setup? I would like to confirm what we saw on the dyno on the lake at start up just for a little peace of mind. I am thinking a portable, handheld kinda thing but have zero experience with such things.

Finally, many thanks to everyone that responded to this thread with insights, thoughts and recommendations. I learned a ton. While the boating content around here seems to get slimmer by the day, it is pretty damn amazing that when someone needs help a bunch of really smart people engage. RDP delivers.

 

[ChrisV]

Motor rebuild is complete, I got it back right before thanksgiving. The good news is, aside from trashing the pistons, most of the motor was undamaged and as new. I elected to do a full refresh; new pistons, block hone, bearings, valve job with new intake and exhaust valves. I had Carson freshen up and reseal the turbos. I took the advice given here using my fuel delivery system for the new dyno runs. Also made sure A/FR and exhaust temp were recorded as part of the process through the full range of throttle openings and rpm. It ran great on the dyno and it's back in the boat.

The root cause of the "too much crankcase pressure" problem was simply ignition timing. My notes from when I picked up the motor back in 2017 indicated that the distributor was locked out and the timing should be set to 30 degrees. That's what I did after pulling the dizzy and priming the oil system when I finally started up the motor for the first time in 2022. As it turns out the distributor was not locked out and the motor was seeing way too much timing. Now, this isn't the first motor I have set the timing on and I definitely know to run up the rpm to confirm total advance but I guess I didn't do that in this case otherwise I could have avoided the "lost summer of '23". Maybe target fixation on 30 degrees? Maybe too much excitement to have the damn thing running after so much time and work? Hell, it sounded so nice running on the hose I couldn't walk right for most of the rest of the day so that's a possibility. Damn if I know, but setting the timing correctly is my responsibility and I have learned (re-learned?) this lesson the hard way.

The weather up here has turned below sweat shirt boating temps so it will be spring before I get her wet again.

Any recommendations on a A/F meter setup? I would like to confirm what we saw on the dyno on the lake at start up just for a little peace of mind. I am thinking a portable, handheld kinda thing but have zero experience with such things.

Finally, many thanks to everyone that responded to this thread with insights, thoughts and recommendations. I learned a ton. While the boating content around here seems to get slimmer by the day, it is pretty damn amazing that when someone needs help a bunch of really smart people engage. RDP delivers.

View attachment 1311779


View attachment 1311778

Badass! As for the gauge, you would need two. Which will be an eyesore because your gauges are classy.

This one is cheap and effective. Maybe install just for break in? Or mount it somewhere that you could open and see. I’ve saved my motor from blowing up even looking at idle. Was leaning out and it was a clogged injector.

Home » Shop » Wideband O2 » O2 Controller » NGK Powerdex AFX - Air Fuel Ratio Monitor Kit - Wideband O2 - PN 91101 - w/ NTK Sensor (replaced by SNSR-00990)

Ballenger Motorsports NGK Powerdex AFX - Air Fuel Ratio Monitor Kit - Wideband O2 - PN 91101 - w/ NTK Sensor (replaced by SNSR-00990) (SNSR-01000) for only $247.99!

www.bmotorsports.com

 

[DiamondDave]

Badass! As for the gauge, you would need two. Which will be an eyesore because your gauges are classy.

This one is cheap and effective. Maybe install just for break in? Or mount it somewhere that you could open and see. I’ve saved my motor from blowing up even looking at idle. Was leaning out and it was a clogged injector.

Home » Shop » Wideband O2 » O2 Controller » NGK Powerdex AFX - Air Fuel Ratio Monitor Kit - Wideband O2 - PN 91101 - w/ NTK Sensor (replaced by SNSR-00990)

Ballenger Motorsports NGK Powerdex AFX - Air Fuel Ratio Monitor Kit - Wideband O2 - PN 91101 - w/ NTK Sensor (replaced by SNSR-00990) (SNSR-01000) for only $247.99!

www.bmotorsports.com

This one is dual channel. Had one on my Fountain.

DLG-1: Dual Lambda Wideband Air/Fuel Ratio Gauge Kit

DLG1 Dual Lambda Kit

www.innovatemotorsports.com

 

[BamBam]

It's a good thing you had IMCO put the O2 bungs in the tailpipes!

I'm happy to see you have the power plant back. It is such a pretty piece.

 

[mattyc]

Motor rebuild is complete, I got it back right before thanksgiving. The good news is, aside from trashing the pistons, most of the motor was undamaged and as new. I elected to do a full refresh; new pistons, block hone, bearings, valve job with new intake and exhaust valves. I had Carson freshen up and reseal the turbos. I took the advice given here using my fuel delivery system for the new dyno runs. Also made sure A/FR and exhaust temp were recorded as part of the process through the full range of throttle openings and rpm. It ran great on the dyno and it's back in the boat.

The root cause of the "too much crankcase pressure" problem was simply ignition timing. My notes from when I picked up the motor back in 2017 indicated that the distributor was locked out and the timing should be set to 30 degrees. That's what I did after pulling the dizzy and priming the oil system when I finally started up the motor for the first time in 2022. As it turns out the distributor was not locked out and the motor was seeing way too much timing. Now, this isn't the first motor I have set the timing on and I definitely know to run up the rpm to confirm total advance but I guess I didn't do that in this case otherwise I could have avoided the "lost summer of '23". Maybe target fixation on 30 degrees? Maybe too much excitement to have the damn thing running after so much time and work? Hell, it sounded so nice running on the hose I couldn't walk right for most of the rest of the day so that's a possibility. Damn if I know, but setting the timing correctly is my responsibility and I have learned (re-learned?) this lesson the hard way.

The weather up here has turned below sweat shirt boating temps so it will be spring before I get her wet again.

Any recommendations on a A/F meter setup? I would like to confirm what we saw on the dyno on the lake at start up just for a little peace of mind. I am thinking a portable, handheld kinda thing but have zero experience with such things.

Finally, many thanks to everyone that responded to this thread with insights, thoughts and recommendations. I learned a ton. While the boating content around here seems to get slimmer by the day, it is pretty damn amazing that when someone needs help a bunch of really smart people engage. RDP delivers.

View attachment 1311779


View attachment 1311778

More pictures please!