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'68 Coronet project EFI/4 speed conversion up and running!

Well, all this PCV talk got the wheels turning - have to think this old guy is not doing much of anything except creating a vacuum leak. Have not gotten around to finding a f.o. type yet.
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The main reason the PCV was out was to pop the valve covers off and see what, if anything was to be seen in regards to my leaks. They're not as bad as I thought but I can see where they were wicking oil in the lower corners. The lower corner bolt threads were soaked with oil so it's weeping past the gasket. These cork gaskets were free and filled in OK but clearly are not up to the task. Plus, now that they're off they're pretty much junk. Have some new gaskets on the way from Summit, ordered two different brands just in case.


Never gave it much thought before but now that I am dealing with these leaks head on, it's obvious why people have been pulling their hair out with this nonsense for 50 years.

.

You aren't going to get those valve covers to seal up with those gaskets. That is stone age technology that you're dealing with.
 
Back with some more updates. More like two steps forward, three steps back.

Had this really crummy thing happen to me for the second time - I cracked a valve cover. I'm really upset about this one, these are made-in-Japan M/T no logo covers which are super rare and in really nice shape. At some point I may take it somewhere to see if it can be repaired. Same thing happened with a set of Cal Custom covers.
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So painful and expensive lesson learned - don't use cast valve covers on OE heads with "modern" gaskets. I should have known better and could have avoided this but obviously was not thinking clearly. When I installed them, I could see a gap between the head and the gasket which obviously would have leaked oil everywhere. Kept going around and tightening the bolts a little at a time with a 1/4" ratchet to see if it would close down but no dice. Guess I found the breaking point. I'm sick over this, just totally pissed at myself.

Luckily I ordered two sets of gaskets from Summit. I used Fel-Pro 1612 on the cast ones here but also got a set of Mr. Gasket Ultra-Seal "just in case". Glad I had the foresight to do that because luckily I had a pair of OE stamped-steel valve covers on the shelf. Cleaned them up, sprayed a little paint and they were ready to go.
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Incidentally, I used valve cover studs with these which worked out well. They are ARP made specifically for use with OE type stamped valve covers. I bought them mistakenly several years ago but never used them because I usually use some type of cast covers.

I also went against my better judgement and used a ton of gasket goop to glue the gaskets down. Definitely fought with it, was oozing out everywhere but in the end, it worked. Took the car out for an extended drive the other day and no visible leaks for now.

I created a different thread about my ongoing power steering leak. Will update here when I get to some sort of conclusion in that battle. https://www.forbbodiesonly.com/moparforum/threads/power-to-manual-steering-box.207688/

In other news - during the most recent drive the other day, I experienced an EFI-related stall issue. It's happened three times under the same conditions; in second gear under light throttle and very little load, like when slowing down for a stop light or driving slowly through neighborhood streets behind a slower-moving car. Also pretty certain that each time it's happened I was on and off the clutch in rapid succession trying to modulate speed. I've seen this discussed on the Holley forums a little. From what I've read, there is a parameter in the software regarding fuel shutoff under deceleration, thinking I might need to turn that off and see if that clears up the issue. I don't have a working PC at the moment, have to get a new laptop screen and unless I partition my Mac to run Windows, I'm SOL. What this means is that I can't get into the software to look at data logs or make any changes so until I get a new laptop screen I'm currently dead in the water on that front.

Regardless, once the conditions are met and it wants to stall, there's pretty much nothing you can do, it won't respond. The other day when it happened I was putzing along at around 20 mph and the engine just shut off like it ran completely out of fuel. Managed to pull it off to the side and thankfully there was little to no traffic this time. Like the times before, it would crank but wouldn't fire again until several minutes later. Was sort of far from home so was relieved when it fired up again.

Looking at the bigger picture, I'm hoping all these mishaps and struggles don't paint a picture of some hapless hack who doesn't know his *** from his elbow. Yeah, some of these things are the result of doing things unconsciously which took a catastrophic event to wake me up. It's been mentioned before but I have to think some of this teething is because I'm trying to re-engineer old, worn-out parts that don't always play along.

Getting colder here and driving fun time is dwindling. Noticed that I've started looking into some parts I have on hand to build a different motor. Not quite sure I'm ready to start on a big project like that right now but the wheels are turning.

Stay tuned.
 
Your story resonates with me buddy! My 69 RR leaks oil, and now PS fluid everywhere, and I've got the Holley Terminator Stealth with oil pressure hooked up to the fuel pressure sensor! Been having trouble getting it to learn lately, and hoping when spring rolls around it should be fixed. I leaned it out so hoping that helps at least, and probably have an exhaust leak somewhere. I know mopars stink like gas, but mine is to the point where if I drive it for 30 seconds my shirt will stink all day!
 
Been a little while since my last entry so thought I should provide an update. It's actually been a typical northeast winter this year so I have not had the car out for almost two months, lot of salt on the roads and it's been cold. Truth is though, I needed a break from the car. The leaks were really getting me down, to the point I didn't even want to look at it anymore.

In the interim, I have been working on some other projects. I bought a welder and have been making a welding cart and also trying to get my workbench closer to completion which does involve some welding. It's been slow going on both but I am enjoying welding. I've been wanting one for years, not sure why it took me so long to buy one.

But on to the car. Back in November I ordered a full set of Speedhut gauges to replace the disappointing Holley EFI gauges. The SH gauges were on sale for the holidays so I went ahead and ordered a custom set and got a decent deal. The nice thing with them is that they allow customers to design their own gauge faces and layouts so I took advantage of that and had them configured the way I wanted them. Couple rounds of proofs with the art department and I now have gauges I designed myself. Nothing fancy, modeled after Autometer Traditional Chrome without the shiny bezels which I thought would be distracting.
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The main issue at hand with installing custom gauges in a standard '68-'70 dash is the height of the instrument panel. I wound up using 2 5/8" housings for the speedo and tach which are relatively small compared to your typical 3 3/8" gauges. A big drawback to having a 2 5/8" speedometer is there is no odometer but as long as I have a working gas gauge it won't matter too much.
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So because of the short panel height, most off-the-shelf gauges really won't fit without major surgery. The solution was to make a custom panel out of aluminum. I used the standard dash blackout overlay as a template for the shape so it basically bolts in the same way the factory part does. The back of the cluster is gutted now just leaving the housing so the panel has something to attach to. The panel needs to have turn signals and a brights indicator installed. On the fence if I want to install a low oil pressure warning light and/or keep the low brake pressure indicator. Then its paint and wiring and back into the car.

Kind of not really looking forward to rewiring this stuff again but it's gotta be done. I really need to have a gas gauge - the last time I had the car out I managed to run out of gas. Fortunately I was pretty close to home but what a PITA. If I had a working gauge it wouldn't have happened.

Also not looking forward to seeing if/how these gauges will play with the Sniper stuff. For the most part it doesn't really matter because the Sniper dash gauges were merely add-ons beyond what the handheld shows. Even though they are very similar (digital stepper) the SH gauges supposedly do not work with the Holley ECU at all. Fortunately, (unlike the Sniper gauges) they come with whatever transducers are needed to supply the data so that essentially eliminates any compatibility issues. The connectors for power/ground/lighting appear to be the same as the existing Holley parts so presumably that wiring can be re-used. Will post updates when I get the gumption up to do it.

Second new item is a fancy M/E Wagner "Dual Flow" adjustable PCV valve. There was recently a group buy on these on Moparts that I managed to get in on so the price was almost $30 less. There is a bunch of info out there regarding EFI and PCV valves and how the 50-year old non-adjustable ones can wreak havoc with your EFI A/F inputs.

So the basic solution is to get one of these fancy valves and run it in closed orifice mode. Seems like a bit of a waste to spend so much coin on one of these things only to use it this sort of simplified manner but rather than trying to engineer something it appears to be a reasonable solution. Not sure what I will be looking for as far as drivability. The ECU is self-learning so if you've had a vacuum leak since day one, your fuel tables will have adjusted to those conditions. Suppose I will have to to remember to save a file before installing the valve to be able to compare A to B.
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Don't see winter ending anytime soon so hopefully I can get these things done before Spring. Stay tuned.
 
Been really nice here the last couple days and got the Coronet out for the first real drives since last December, have some updates to share.

To be honest, the first outing was a little demoralizing. Late last year the car developed an unsettling throttle "hitch" which was making it difficult to drive. You'd press the pedal down and it was like driving a car with a slipping transmission - she no go. But then suddenly you'd reach a certain point in the pedal rotation and it was like instant WOT. To make it more confusing, the condition was never where you'd expect it to happen. Not good! Don't know how it happened because it wasn't there when I first started driving the car. Guessing I must have taken the throttle cable off for something but failed to put it back in the exact same spot on re-installation. I dunno.

Before winter set in I tried adjusting the cable once or twice to no avail. The car was running OK otherwise so I didn't suspect it was something with the EFI. Today I went back and looked at the cable again, paying closer attention to the throttle lever actuation. There was no real discernible spot where you could feel anything weird but after a few minutes I ended up pulling the slightest bit of slack out of it. I mean yeah, basic stuff here but that seemed to do the trick because acceleration is nice and smooth now with no hesitation then instant WOT. The entire range of drivability seems to have improved or, at least it feels that way. Not sure if the Sniper is more sensitive to cable adjustment than a carb. Perhaps the TPS is reading 40% but because of that little bit of slack it's in fact only at 38.2% or something... or maybe because there's no accelerator pump to cover it up...who knows. Whatever I did it's OK now.

So about those pesky fluid leaks. Oil pressure is good and the crankcase is full but there is still a decent size puddle of oil under it after each drive. Checked the fitting for the mechanical oil pressure gauge line at the back of the block and sure enough, it was loose. I know I checked/tightened it last year when it first started leaking so it hadn't occurred to me to check it again. Cranking it down seems to have helped somewhat because after parking it this time there's only a few drops rather than a puddle. Might even be residual so gotta put it up in the air, clean it all up again and hope for the best. Still going to be a pressure fitting there but the mechanical gauge and copper line is going bye-bye when the new gauges go in. Guess we'll see if the leaks continue.

Speaking of oil leaks, the new Wagner PCV valve is in. Before I put the valve in, I made a few small changes to the EFI idle settings. Checked the manifold vacuum, was around 14-15" at idle. In gear it dropped like normal but I don't remember to what. While checking the vacuum, I noticed the idle was pretty rich because I could smell it and my eyes were burning. Went online and read up on idle tuning and learned that the default idle "target" AFR is 12:1 = rich. I changed that parameter to 14.2:1 which certainly cleaned it up. Not quite stoich (14.7:1) but not 12:1! Vacuum did not change really but at least my eyes were no longer burning. Kept the idle timing the same. I did try bumping it a few degrees to see what would happen but the vacuum didn't really change. I might try to increase the idle timing again but I left it at 17 for the time being, one thing at a time.

But back to the PCV valve. Honestly, I'm not noticing any real change in drivability with the PCV though I'm not sure there would be noticeable changes in performance. The valve is in "fixed orifice" mode so it does not work based on engine load. I have not looked into the data tables to see if there is any drastic change but I'm guessing there isn't anything to write home about. I really need to get a working PC for on the fly tuning. Tried fixing up an older one I have but it won't hold a charge. May try to find a cheap one just for having in the car.

Well, still an uphill battle trying to iron all these things out but things are heading in the right direction for once. Until the next entry...
 
Idle tune is still the same as with carb, afr and timing for max vacuum reading.
You might unplug the iac to ensure it's not compensating while you're tuning.
You would not expect 14.7 for idle. I think my fury is at 13.5 but each engine has it's own needs.
 
Just adding a little update on my thread here. Got back on the gauge panel and mocked it up in the car. It's not perfect but it's decent enough and fits nicely. Took a lot of whittling with a file to get it to sit snugly inside the OE bezel housing. The bottom of the gauge bezels are a little too low. Not sure if I'm going to leave it alone or try to adjust it so they look more centered top to bottom but there's not a lot of room anyway with the dash trim installed. Panel has to be wired, indicators installed and then paint. It should look OK when it's painted.
IMG_1513.jpg

That's all for tonight!
 
Yeah, I’ve seen those, they’ve been around for a while now. I just can’t stand the way they look. You’d think there would have been more effort towards making them “look the part”. Its mostly the odometer and clock, they look so generic and out of place.

Plus, they are about a grand. My Speedhut gauges were $625 and I designed the faces myself.
 
Little more progress on the instrument panel today. The face of it is done. Turn signal and brights indicators installed, obviously painted. Wiring is going to be a PITA. The previous Holley gauges had a lot of wires extending all over the place. I have a problem leaving unused wires just hanging or even just tucked into the rest of the harness. Was looking at it today, I know there's the potential for me to take the entire harness apart again just to get at the unused wires. We'll see how nuts I get with all that. That's all for now.
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Yeah, I’ve seen those, they’ve been around for a while now. I just can’t stand the way they look. You’d think there would have been more effort towards making them “look the part”. Its mostly the odometer and clock, they look so generic and out of place.

Plus, they are about a grand. My Speedhut gauges were $625 and I designed the faces myself.
I agree, it's like putting a 1991 f150 gauge set in there!
 
I agree, it's like putting a 1991 f150 gauge set in there!

I don't know how much "better" my setup is but it's definitely less generic. I opted for modern-looking black bezels instead of brushed aluminum to cut down on glare. Not sure if that's going to matter since the gauges are under the dash overhang but the less distractions the better.

Speaking of distractions, the brights indicator turned out out to be kind of a pain. I had a blue LED for it but it was way too bright, couldn't have it in my face while driving. Behind that half-assed painted washer in the middle is a piece of blue tinted Mylar (?) from another dash indicator which I glued behind the hole. Behind that is an LED which the Mylar helps diffuse. It actually worked out pretty well. I have to make a bracket for the light socket but that should just be a piece of aluminum to line up with some already-drilled holes.

I like to make more work for myself.
 
Continued working on the gauges today. Got the wiring done to the point of having power and lights. Did a quick connectivity test to make sure all the lights work, see below. I really like the way these look lit up, will be a huge improvement in visibility over the OE cluster.
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Have to run the coolant temp sender and oil pressure wires through the firewall to their respective connections in the engine bay and figure out the tach sender wire. The Holley Sniper ECU has a tach output provision which I was using already with an Autometer tach I just have to figure out where I ran it under the dash.

Dealt with the GPS speedometer cable today as well. I figured out a way to mount it on the dash and have it be a little less conspicuous. It needs to be facing up and must be unobstructed so it picks up a satellite signal. The instructions say you can actually put it on the roof but no way I'm doing that.

Anyway, the little GPS signal pickup module has a magnetic backing so it sticks to the dash surface. It has a long coaxial type wire running off it that routes to the speedometer itself. Didn't want to drill any extra holes in my dash so I ran it under the defroster vent. Had to file the edge of it down so it dosen't chafe the wire but the vent was broken already so I didn't feel so bad about it. Worked good. Just have to order a block off plug for the trans now and bye bye noisy and cumbersome speedo cable.
IMG_1617.jpg

Trying to get this task done relatively quickly so I can get to some other stuff that needs to be taken care of on this car. Not sure if I still have an oil pan leak or it's the rear main seal but last time I drove it a few weeks ago there was a larger-than-normal puddle of fluid underneath. I have a feeling it's the pan but it's hard to tell. Just not looking forward to taking the pan off again. Something is telling me I need to pull the engine but I'll probably just try to manage it for now and see if I can get through this season. That's really the only thing keeping me from driving it daily.

More to come.
 
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check your oil pressure sending port on top of engine. mine backed out just enough to flow oil only when driven then would clear up when parked. after tightening my oil leak when away n things are bone dry.

great looking gauges. nice work!


watermelon
 
Thanks! I do like these gauges. I wish the panel had a little more style but at least it's functional.

Regarding the leak - I've been battling seeping fluids since the day I took ownership of this car. The Speedhut oil pressure gauge uses a transducer that screws into the OE oil pressure port. When the old can type sender was removed to put the transducer in, I checked the ports for leaks, both were dry. Something could be leaking from the top side but it's hard to tell where it could be coming from.
 
That looks damn cool!

You should offer that cluster with a few versions of harnesses to replace either the stock ones or with upgrades like the Sniper. I’m drooling over that EFI.
 
That looks damn cool!

You should offer that cluster with a few versions of harnesses to replace either the stock ones or with upgrades like the Sniper. I’m drooling over that EFI.

Well thanks! I don't know if making something like that is in the cards for me but I appreciate the kind words. It's true that besides the Dakota Digital option, there's basically nothing out there to replace a standard 68-70 B body dash so it would be good to have another choice. Your idea about offering different types of harnesses makes sense but I think it would probably just end up being generic. The digital gauges use low voltage wiring with these tiny little connectors, now way you'd be able to plug it into an existing harness.
 
I had to break away from the thread only a post or 2 in on the 2nd page, and I'll pick it back up tomorrow if I can.
This may have been fixed by now, but my FIRST and by FAR formost thought on all those engine oil leaks was "PCV valve non existent or not working properly." Crankcase pressure (excessive) will definitely make it leak!
I also just switched from manual steering to the power steering unit that CVF supplies with the Wraptor serpentine belt and accessories system. It's a GM II PS pump, which according to CVF does NOT have to be restricted (pressure) to work w/my Borgeson PS steering box. It was noisy, a lot, coming out of the garage which requires sharp turns immediately. I checked the fluid level hot, cold, etc and it seems to be quieting down with time, and it only does it at first.
I have a recent American Powertrain hydraulic throwout bearing conversion kit, I hope you figured it out, and I look forward to reading more. Mine was "sticking" a bit, in the RXT dual disc assembly I believe, and that made it seem like it was not fully disengaged, but that has "self resolved":bananadance:
Great setup, beautiful car!
 
Great setup, beautiful car!

Thank you. Keep reading through it I guess, most of the same issues are still ongoing to some degree.

I'll say the one thing that has not come up again is the T.O. bearing. Honestly I don't even think about it, it just works. I spoke with A.P. about it, the bearing is not supposed to retract the operation is similar to how disc brakes work. The bearing rests on the clutch fingers like caliper pistons would on a spinning rotor.

Still battling the fluid leaks though the power steering seems like it has been less than at first. I ended up making my own return line and tightened the crap out of the fittings, have not seen any leaking lately however I have not driven it for a couple weeks so that may be why!

On the oil - went through a whole PCV thing already, not really any visible difference. Does not seem like the rear main seal. I popped the bellhousing inspection cover off yesterday, dry as a bone. Oil pan bolts are still tight. Part of it is coolant running down the sides of the block, the header bolts leak, even with sealer on the threads. I used as many studs as I could. However, oil is definitely coming from somewhere though! I need to clean it up again and when I get it back running will have to try and pinpoint where it's coming from with dye or powder or something. Could be the back of the intake? Who knows.

Frankly though I think it leaks because the motor is just plain worn out. That may sound silly but it keeps popping into my head as a valid reason so I'm going with it. The P.O. of the car said he rebuilt it but given the other butchery I've found I'm pretty sure he was full of ****. To that end, when I drive it, I don't just putt putt it around, I drive it like normal and try to get on it as road space allows. Things are basically fine while driving - no smoke or oil pressure issues, does not overheat. It's just when you park it and everything cools off the leaks start. Like I said in a recent post I think the engine needs to come out, you can only do so much while it's in the car.

Thanks for reading.
 
I'll say the one thing that has not come up again is the T.O. bearing. Honestly I don't even think about it, it just works. I spoke with A.P. about it, the bearing is not supposed to retract the operation is similar to how disc brakes work. The bearing rests on the clutch fingers like caliper pistons would on a spinning rotor.
Right!?! MIND BLOWN!!:BangHead: :realcrazy::bananaweed::fool:
When my car was behaving as though the clutch wasn't fully disengaged, I thought it was a problem with the hydraulic throwout bearing. It's SO counterintuitive in that it does NOT have an air gap between the bearing surface and the diaphragm spring tips! Making my concerns worse was my failure to make sure the previous mechanical TO bearing had enough of an air gap, which meant that it was soon spinning all the time and rapidly wore to making noise. The American Powertrain hydraulic throwout bearing is designed to REST (KEY word! as you wrote) under no pressure, on the spring tips. This means no "slop" and a very precise feel to the pedal. The AP rep said many new cars are like that. People prefer the feel as well he said.
Maybe the bearings are made of "unobtanium" to hold up to spinning constantly, but I finally accepted that as truth.
I got lucky that whatever was "rubbing" on my dual disc McLeod, or "whatever" was making it barely creep in gear, clutch pedal all the way down, and act during shifting like the clutch was not fully disengaged, I have no idea (I wish I did) self-resolved. It was installed by a shop, and it was a steep learning curve, and I wasn't looking forward to pulling it all apart to figure it out.
Now I can get my HitMaster launch control system dialed in for the launch, and start making adjustments to my new traction and suspension components!
...if I ever get the time to go to the track...:rolleyes:
 
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