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'51 Mercury gets a 4bt!

15K views 33 replies 7 participants last post by  Brian F 
#1 ·
Hey guys, so you my remember my build thread I started about putting my P-pump 4bt into my 1934 Ford pickup rat rod (here). Well, I was coming up with issue after issue, and overall just decided it would be best to leave it as a gasser and put a flathead V8 in it down the road. Of course I still wanted to do a 4BT swap into something, and had a Jeep YJ lying around, so I looked into that. As far as axles, transmission, and other issues (I have the measly 4 cylinder so nothing is strong enough for a 4BT) I decided not to go that route.

Before I get into details of other stuff, I better give you guys a rundown of my motor. I want a good amount of power and wound up finding a P-pump CPL 1839 about 40 minutes from me, the turbo needed a rebuild and it seemed like and injector or two were "off" but it was a solid deal so I went with it. I picked up an HE351CW turbo (I know people say it's too big but I want compounds down the road), A1 head studs, CrewCab59 rebuilt my injectors, a 4k gsk, 60 lb valve springs, flipped and chopped 6bt manifold, kdp tab, and ported whatever I could get to. Once I figure out a good piping solution, I will rebuild the HX30W and throw on some compounds. I wish someone made a kit haha.

While researching into the Jeep I came across an awesome find on craigslist that I just had to pick up. A 51 Mercury on a 94 F150 frame that is boxed and all custom made tubing from about the firewall back. It is sitting on airbags and the frame will act as an air tank. It came with a lot of parts so I decided to go pick it up. Little to my knowledge, it still had the 300 six and M5R2, which ended up being awesome! When I got home I did some research and found out the M5R2 will bolt up with a Ford adapter, and the motor should mount easily.

I found an adapter plate, starter, and flywheel on Craigslist about 6 hours from me but coincidentally my uncle was traveling up there the next weekend, so he picked them up for me. The flywheel was machined when it got back, I put a new slave cylinder in the transmission, along with the strongest PAC clutch I could find on Rock Auto. Bolted it all up and I am missing the starter spacer, so I rigged something up for now (will be getting a spacer in the future, just need to find one that isn't crazy expensive). I had the filled big rubber motor mounts so I went to the junkyard and picked up some of the correct 45 degree angle ones along with an Astro van hydroboost setup and front calipers.

Right now I am trying to figure out how to go about making motor mounts, as my engine came out of a Freightliner MT35 so it has 90 degree mounts. The frame that will be used as an air tank has two triangular holes that need to be welded shut then it will be ready to go. I need to pick up some steel line for brakes, along with some line for fuel (how big should I go? the lift pump has 1/2" rubber coming off of it). I'm going to put a little list below of parts I need/parts I have to get rid of in case anyone wants anything, has something I need, or would want to trade.

Thanks for reading!! I will be updating very often as I would like it driveable soon and spend basically all my spare time on it. More pictures will be up when I can take some later today.





First start video, one of the lines were leaking so I think that's the reason for white smoke http://youtu.be/ET6xoiHFuEY


Parts needed:
94ish F150 clutch master cylinder line (the one with "quick release" fitting to go into slave)
Ford adapter starter spacer
Ford motor mounts (maybe, depends on measurements)

Parts I have:
Eaton FS4205
14" (I think) clutch
Flywheel
SAE #2 adapter
Starter for said adapter
4k gsk brand new in the box
 
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#2 ·
Neat project. That HE351cw is a great single turbo for a 6bt but the 4bt will have a hard time spooling one that big. The compressor in that one is the same as an HX40. The original turbo that came on your engine was an HX30W which is one of the two best turbos you can have on it. The other would be the HE221W. Not even sure the HW351cw will work as a low pressure turbo in a twin set. That 9cm turbine housing is awfully small. There are some guys working on testing that theory. Love the old Merc.
 
#3 ·
Thanks for the input! Do you think a smaller exhaust wheel, maybe 54 or 56mm, would work better to spool it? Or if I went twins would a 12 or 14 cm housing work better maybe? How much power can an HX30W support? It just looks awfully tiny to me so I'm afraid it will run out of steam after 2k rpms. I guess I should probably look at a compression map for one if I can find one.

This whole motor mount issue has me a bit stumped. I wish I just had some of the Ford style 45 degree ones, does anyone have some laying around they could part with? If I make my own I'm afraid I will either A) make something off that will effect something else and B) not be able to find some sort of a rubber mount. I've seen some people use the rubber piece that came on their ford setups, and some people use first gen Cummins mounts. Any recommendations there?

I am picking up my rear sump oil pickup tomorrow from the local Case dealer, so I will have that ready to go and the engine oil in. Probably will do another start just for the hell of it. Once the motor mounts are figured out I will be tackling the rest of my air suspension, pedal setup (will be hard to fit the hydroboost setup with the way the frame is close to the firewall), then brake lines. Hopefully I'll have it able to scoot down the road (kind of) in the next week or two. Thanks again!
 
#4 · (Edited)
Turbos are one place where bigger is not necessarily better. As a single, the HX30W can go 250 hp or maybe more. There are at least 3 different compressor wheels on HX30W. There is a 40mm, 44mm, and 50mm. The 50mm is referred to as a Super HX30W. You don't want a much larger inducer than 50mm on a 4bt. The best turbine housing seems to be the 6cm. Yes, those look tiny but they are power makers. The secret is the smaller turbo builds boost quicker to allow the engine to burn the fuel producing more power and lower exhaust temperature. The other turbo that has become popular is the HE221W which is even a tad smaller. That one uses a T25 exhaust flange and would require an adapter to mate to your T3 manifold. The HX30W is T3. As for twins, there is tons of info on the forum about what works well. The current popular set up is the HX30W-6cm paired with a Hx35W-12cm. Those two can produce boost that will cause you to make engine mods to handle it. If you don't need much more than 30 lbs. boost then the small single is the ticket. If you want in the 35 lb. plus range then twins come into play. There are several excellent thread about the different turbos that you can read.
 
#5 ·
I did a lot of turbo reading over the last few days and decided I'm going to order a rebuild kit for my hx30w, I'm going to try it as a single. Then go compounds after I'm assuming. I made some progress on the build. designed and built some motor mounts then had a buddy weld them up since I have the skill of a toddler (for now). I flipped the oil pan and got a rear sump pickup. Everything is bolted in, driveshaft in, tranny bolted down, it should be all good to go.

Tomorrow I am going to try and find an adapter for the 1/4 flare fitting oil line (for old oil pressure guage) to a 1/4 npt fitting so I can use my aftermarket guage. I drained my oil after running it because I had to flip the pan, and it smelt strong! I wasn't sure of the smell, maybe diesel? So I picked up a 5 gallon pal of more rotella, got home and opened it up, sure enough same damn smell. Doesn't smell like the synthetic castrol and Mobil 1 I'm used to putting in my German cars or the random oils I throw in my small block chevy. I'm just glad there isn't diesel leaking into the oil.

Anyways, I'm hoping to figure out my pedal setup this weekend, and pick up a new clutch master to sale cylinder line since the quick release was stuck and I had to cut it off. Brake lines are still on the list but I've been putting them off even though they shouldn't be too hard. Thanks for reading.
 
#7 ·
This is a great swap project that you have going and please keep the momentum going in it. Hopefully you don't have too many significant hurdles up ahead to clear. Please keep us posted on your progress as well as challenges.
 
#8 ·
Thanks char1355,I read through it and have the turbo pulled apart, now just waiting for my kit.

Thanks ya Brian, I had a few hurdles in the last week but have seemed to somewhere get over them. I made a pedal mount set up that seems like it will work great after lots and lots of tries, and have just about the entire brake system done. I am waiting on two pressure relievers or whatever they are called (long day, I can't remember haha) and they should be in tomorrow. I have to rebend my radiator mount area up front because when I unloaded it from the tilt back trailer I left a hook on it and it bent right down. Once that is out of the way, I have a 49 Ford radiator I should be able to use. The inter cooler is mounted up and I just need to make brackets for that. The fuel line is ran, but I need to run the return line still. Then comes the oh so fun wiring of lights, compressor switches, ect. I'm hoping for a maiden voyage over to my buddies to use his welder to weld some tac'd areas.

I think my biggest issue right now is probably my clutch pedal... I don't really have one to use. The master cylinder has to w mounted level and my pedal mount system is at 120 degrees (like this \_ ). If anyone has any ideas input is greatly appreciated... I will see if I can post pictures tomorrow. I ended up using the astro van brake and gas pedals since they are much smaller than the F150 ones I had. Thanks for reading!
 
#10 ·
Yes sir, I really have a thing for flatheads and was on the fence between a supercharged flathead or the 4BT, but just thinking about these long and pretty heavy cars, the torque of a diesel is just fantastic for them. Lead sleds were never really all about drag times or anything like that, and I'm sure with the driveability will be improved with the 4BT. Seems like a logical swap! If you can get past it not being "period correct," that is.
 
#11 ·
Mr. Grizz,

With what so many of us on this forum have done to our beloved vehicles for a variety of convoluted reasons, it'd be tough to find anyone in the audience who would consider your swap to be illogical. Your project actually makes mine look like a walk in the park. Keep fabbing, wrenching and dreaming.

Brian
 
#13 ·
Thank you. I finally took a peek at your project, I love it! It is extremely clean, I have a 68 Firebird I was considering doing the swap in, but just didn't see there being enough room without huge modifications. I see you are from Wisconsin, I am in the southern part (Janesville area), and my parents are from near Hayward. Where are you located?

i'm not really into that "period correct" deal, otherwise you'd probably get kinda restricted to either a detroit or a perkins...
Ah yes, I am glad I went with the little cummins though, I went into the project not really knowing anything about diesels and with the help of this amazing forum I have learned a lot, and am actually considering switching my degree over to a diesel mechanic or something similar.

As for updates, I don't have a whole lot. I finished the rest of the brake lines, but still don't have the pressure valves, so that isn't. Still am trying to figure out a clutch pedal, I am kind of stumped really. Labor day weekend going on means my favorite car store around here (the one that actually has knowledgeable and is family owned) is closed up. My wifes half sister has cancer and was given a few days, so that puts a dent in progress too. Hopefully I can get something figured out with the clutch and such without spending $200. I am into this project a lot more than I was expecting! But that isn't anything out of the ordinary haha. Have a good one guys!
 
#14 ·
Mr. Grizz,

Heck, your parents are practically in our back yard. We live about 10 miles west of Highway 53 just a bit off of Highway 29 in the Elk Mound area and occasionally make it up to the Hayward area. I always like going up there for a little solitude (and of course the world famous fudge).

Hang in there with your Cummins conversion and please accept my condolences regarding your wife's half-sister.

Brian
 
#16 ·
Ah that's pretty close! They are close to Ladysmith, I just say Hayward because people seem to actually know where it is. Maybe next time I am up (possibly even with the Mercury), I could stop by and check out your Plymouth! The wife's sister passed this morning sadly.

for the pedal assembly take a look at the speedway catalog---they have 2 styles--firewall mount and floor mount--everything hydraulic--modular--easy to install....
Thank you! I almost pulled the trigger on the floor mount set up, but actually decided to create my own frankenstien to go with the rest of my pedal set up. I will post pictures tomorrow.

In the meantime I have received my brake residual pressure valves, so they are installed and the entire brake system is good to go. I figured out a mounting system for the radiator and intercooler, so that will be installed probably tomorrow. Then it will be time to fill and bleed everything, and hopefully go for a test drive! Ah how exciting. I wont have the airbags on switches yet however, so that will have to be done soonish too.
 
#18 ·
The set up I came up with uses a firewall mount so thankfully I won't have to worry about that, lucky thing I didn't go floor mount or I wouldn't have even thought of that. Thanks! I picked up a 2 psi residual for the discs, and 10 psi for the rear drums. Will that work? I saw someone use a similar setup on the hamb. Also, does anyone know where to get a custom sized clutch line for an m5r2? The stupid Ford "quick fitting" style. Or if there's an adapter out there to go to a standard line, that would be cool.

Thanks for any help!
 
#20 ·
Thank you! I can't wait for a chop to be done.

Well. I have a bit of an update guys, I figured out that it is a 1990 Ford F150 frame, not 1994, which explains my brake issue I was having. So I have an even bigger problem now... I bought a 52 dollar clutch line and ordered it for a 90, as I figured it would be the same. Nope. Dead wrong. The slave cylinder I put in the transmission is for a 94 and is the plastic style instead of metal style one. If I use pick up the correct style clutch line (94) will I be okay? Or do I have to rip everything apart again now that I'm so close? Any Advice is more than welcome... I hate set backs like this.
 
#21 ·
Mr. Grizz,

Sorry to learn of your sister-in-laws passing. I'm certain that you are being called to support your wife through this time of loss.

If you're ever passing through the Chippewa Falls area, feel free to drop me a line at grease_dynamism@yahoo.com. It'd be awesome to rendezvous with you at the Leinenkugel Lodge where you can show me the ins and outs of your 51 Mercury restoration/swap project (even if it is just pictures). Until then, keep up the momentum on it.

Brian
 
#22 ·
Thank you for your condolences, and that would be great! My two brothers live in Eau Claire so I am that way often. Looking forward to meeting up sometime.

Well guys, I have some updates. I had to get some hoses made for my power steering/hydroboost setup, and had to figure out my radiator hoses. After a lot of trial an error I think we are all good to go. Boy everything has taken a lot longer than expected! I guess that's what happens when you start out with nothing done haha. I have some pictures finally, so you can see my progress. I know everything is rusty, nasty, and dirty. But I kind of like it that way, I'm sure I'll get around to cleaning everything up and such one of these days.

Just kind of a side shot of the engine



Motor mount



Intercooler/radiator



Lots of hoses and other junk going everywhere



Hydroboost setup and clutch master cylinder (such a pain to get everything to fit, since the frame was right in the way and couldn't go under the floor setup)



Power steering/hydroboost reservoir



My (poorly) designed custom pedal setup haha



Dash and stuff, need to make a firewall and put in my floor pans



Rear floor area, neat driveshaft cage. I also have a cage for the transmission but had to cut it out.



Tubbed



Fuel take with pickup and first filter



Bonus of the 34 and Merc together



Thanks for reading guys! I'm always open to suggestions/comments/concerns. Have a good one!

Mason
 
#23 ·
save room for ALOT of sound deadening material in the merc. I used two layers of "FatMat" on the firewall and floorboards of my truck.... three layers wouldnt have been a bad idea..... these old cars have a lot of metal...... Neat project!
 
#24 ·
Sounds like a good plan! Do you recommend FatMat over Dynamat? Or any other brands? I'm trying to find the best for the money, as saving some money would be cool. Part of me wants to do something cool like plexiglass floors, but then again it wouldn't be very quiet for the wife and baby haha. My truck doesn't have any sound deadening material or even windows, so it's plain old loud to ride around in!
 
#25 ·
Making great progress. One problem I see. You have an HE351cw turbo on that engine. Great turbo for a 6bt but a 4bt will never spool that one properly. Way too big. You need the HX30W which was stock on the P pump 4bt. Will give you far better performance. The engine won't be very happy with the big one.
 
#26 ·
Yup! I'm still waiting for this rebuild kit, just have it on to make it down to my buddies shop in the next few days. He has more resources to make piping for the compound setup I'm going to go with. I decided after doing some research on the HX30w by itself that I think I'll be happier with compounds, so I'm going to see if I can sell the he351cw and pick up an hx40 to go over the hx30w. Should be a pretty killer setup if I'm right!
 
#27 ·
The HX40 has been used in a twin set up. Sort of depends on how much power you're going for. The HX35 has been a proven unit for twins and lots of guys have been using it with great success. The HX40 might be a bit slower to come on but could make a lot of power. Sort of depends on how much fuel you're going to feed it. Actually, the HE351cw has an HX40 compressor, but the 9cm turbine might be a bit restrictive for twins. Try to find an HX40 with the 16cm turbine housing.
 
#28 ·
Seems like I chose FatMat due to the improved vibration resistance. It was about the same cost. Although my truck is not quite, it isnt bad for a 50 year old truck with a diesel known for vibrations
 
#29 ·
Okay great, I'll have to look into it!!

The HX40 has been used in a twin set up. Sort of depends on how much power you're going for. The HX35 has been a proven unit for twins and lots of guys have been using it with great success. The HX40 might be a bit slower to come on but could make a lot of power. Sort of depends on how much fuel you're going to feed it. Actually, the HE351cw has an HX40 compressor, but the 9cm turbine might be a bit restrictive for twins. Try to find an HX40 with the 16cm turbine housing.
Well, I have 5x12s from CrewCab59 and may pick up some delivery valves in the future. I'm not sure yet really, but the more the merrier. How close are the he351cw and hx35/40 in dimensions? If I made piping and all for the hx30/he351 setup, would I be able to bolt in an hx35 or hx40 in its place? Just in case my egts ended up being too high with the restrictive 9cm housing.

I got a little bit of work done today, I'm jut trying to figure out my steering right currently. I fired the engine up and let it idle for a whole today, searched for leaks and figure out I didn't torque my injector hold down nuts well. Ended up getting that resolved, putting a new washer between the return line banjo bolt at the filter, and found a leak in the rubber hose from the injection pump to the filter. I'll be picking up a new one tomorrow. Hopefully the engine will be running well then.

I went through two ignition switches today, I'm assuming too much load for the pull solenoid and starter at the same time. So I will wire that differently tomorrow. But I had one really odd thing happen. I think my engine tried to run away? I'd call it an idle away... It didn't rev or anything, but it just idled and I had to end up choking it out to kill it. Cut the power and nothing happened. I started it about 5 to 10 times with the intercooler piping, revving and everything with no major issues (other than the air in the line that I addressed after this issue). After the incident I disconnected the intercooler piping from the intake horn and started it/ran it/idled/revved about 10 more times and I couldn't repeat it. Does anyone have any ideas? The turbo return line was free and flowing, nothing was coming out of the plastic tube on the drivers side. I'm stumped. Thanks for any help!

Mason
 
#30 ·
On your ignition switch, you shouldn't have much load on it. The start/stop solenoid on the IP has to use a relay. Too much current draw for the ignition. Not surprised they burned up. If you want a real nostalgia look on the old Merc, you can use a manual shut down cable in place of the start/stop solenoid. I bet the Mercury had a choke cable on the dash. That would be perfect. One less electrical problem to contend with. Not sure what the high idle problem was. A runaway occurs when the fuel overrides the governor or the engine starts sucking and running on oil from a blown turbo oil seal. Maybe it just hadn't run in a while and took a bit to settle down. Have you installed a higher rpm governor kit? Not sure whether you'll have to do any mods to your IC plumbing. If you're running twins, the IC pipe will be connected to the HX30W which has a 2 1/2" outlet. If you have 3" pipes it might need some reducer boots. Compared to the HE351cw you have on there it is tiny. Need to look at Lonno's build for what a twin setup looks like. The HX40 is similar in size to your turbo but is quite a bit heavier. Usually the plumbing is the last part of the puzzle so you can fit it to the turbo. There are many other recent builds for twins that will show your what you need.
 
#31 ·
I picked up a relay yesterday and we are all good now! I figured I would, but wasn't sure. I have the old pull style parking brake, I think I might end up using that as my pull. I'll look for a choke cable when I get out to it today, that would be cool too, as long as it pulls far enough. I still haven't been able to replicate the whole "idleaway" issue, so that's pretty odd. I do have a 4k governor spring kit installed.

Last night I traded my HE351CW for a HX35, so that is what I'm going with for now, until I rebuild the HX30W and can come up with a good twin set up. Everything won't fit under the hood, so I think I'm going to just cut a big hole in the hood and have the second turbo above the manifold one. So that's basically what you will see when its coming down the road haha. The intercooler and piping I have is all 2.5" out of the breadtruck from the motor, so everything fits there. I'm going to continue looking at everyone else has for a set up and see what I can figure out!
 
#32 ·
Hi Mason.

I really liked the pictures that you submitted and your progress is remarkable. The charge air cooler that you set up is about as efficient as one can get. Let me know if/when you make it up to Eau Claire to see your brothers and I'd be pleased to meet you guys for lunch.

Keep fabbing and wrenching,

Brian
 
#33 ·
Thanks Brian! Hopefully I'll be able to make it up someday soon, I was supposed to this weekend but my job had other plans.

Well. I bought a painless wiring kit and all sorts of other goodies and have driven her down the road about 20 to 30 miles so far. But she isn't running right. I know I still have to change my timing, but she idles great and everything, until you get on it. Then there's some popping and some white smoke. I just got done searching for air leaks and replaced all of my lines (I did find one leak before the lift pump and tool care of that). I haven't driven it since I fixed that leak, but I am still getting air bubbles when I Crack the injectors! I have a clear hose coming into the lift pump, and there is no bubbles whatsoever. I rtv'd the fitting that screws into the lift pump just in case but that didn't change anything. I put a clear hose on the return off of the p7100 and there is definately bubbles coming out. When I Crack the lines on the pump it bubbles too. What gives? I thought everything after the lift pump is pressurized and would leak rather than suck in air? I have a new overflow valve on it, new line from the filter housing to the p7100, new filter, everything is new. I have to tap my banjo bolt for a fuel pressure gauge but didn't have time today so hopefully can later this week. Does anyone have any ideas? I'm stumped as of right now. It's like the pump itself is leaking. ���� thanks in advance for any advice!!
 
#34 ·
Hi Mason,

I haven't checked in on the forum lately and see that you're having some difficulty with the engine. Did you get such sorted out yet? Did the fuel pressure gauge get installed and yield any indications of a leak-based issue? We're getting ready for old man winter here in Elk Mound, but if you decide to come up to the Eau Claire area, feel free to give me a holler at grease_dynamism@yahoo.com.

Hang in there,

Brian
 
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