Another BFN Rebuild

wakeboardin2k4 wrote: 95000 mile oils not burnt, was low but no apparent leaks. First time it slipped was 4th gear going up a hill on the highway with my trailer and empty barracuda behind it. Maybe 2000lbs. Did 3 fast slips in a row before I let off the throttle for it to catch. Otherwise it's done it mostly in second gear with no trailer on the truck. Has slipped maybe 6 times in the past week.

I hate to add to thread hijacks, but I like to speak up when I can. The earlier style fords had way more torque than the transmissions could handle. I'm not as versed on the internals as Eric but I don't know of many people that haven't replaced or rebuilt transmissions in those trucks. My father in law had to replace his in '86 twice before 200,000. Not sure if they offered a manual in 95 but it is the way to go with Ford diesels...or retrofit an allison .I've been told when towing especially in hilly terrain to shift up and down manually. The rest on those trucks is pretty bullet proof except for the water jacket around the cylinders tend to rust through. My dad had to sleeve his old 6.9 which is the same block as a 7.3.

wakeboardin2k4 wrote: politicallycorrect wrote: wakeboardin2k4 wrote: 95000 mile oils not burnt, was low but no apparent leaks. First time it slipped was 4th gear going up a hill on the highway with my trailer and empty barracuda behind it. Maybe 2000lbs. Did 3 fast slips in a row before I let off the throttle for it to catch. Otherwise it's done it mostly in second gear with no trailer on the truck. Has slipped maybe 6 times in the past week. I hate to add to thread hijacks, but I like to speak up when I can. The earlier style fords had way more torque than the transmissions could handle. I'm not as versed on the internals as Eric but I don't know of many people that haven't replaced or rebuilt transmissions in those trucks. My father in law had to replace his in '86 twice before 200,000. Not sure if they offered a manual in 95 but it is the way to go with Ford diesels...or retrofit an allison .I've been told when towing especially in hilly terrain to shift up and down manually. The rest on those trucks is pretty bullet proof except for the water jacket around the cylinders tend to rust through. My dad had to sleeve his old 6.9 which is the same block as a 7.3. It was the crank position sensor. What was actually happening was a power loss that felt and appeared like symptoms of a trans slip. In regards to the water jacket, a-men to that brotha! Except mine came through the side of the block. I am hoping this trans lasts. I had a trans shop take a look and they said it's fine.

Crank sensor,*************** technology! Whole lot better than a new tranny though!!!

Tim, just curious, how did the overheat condition wind up resulting in a hydro-lock.

Did the overheat cause the exhaust manifolds to fail > which then allowed water in through the exhaust > which then caused the hydro-lock?

Tim, thanks for the visual shout-out there. That was a fun ride.

What really struck me about this boat (and maybe this is just a standard BB thing) was just how casually the boat ran 40mph. My 351 definitely is "working" at 40+ mph, and this boat just loafed. The boat didn't really let on that it was doing ANY work at all until it got in the 50's. Love that! Even after 7 miles of it, the "casual" 40's cruising never got old. Seeing a pair of Airguides just slam into the pegs simultaneously is also quite a treat!

is the cam lobe wore like it took time or does it look like a fracture that happened quickly? id be really interested in the results from Comp, I swore them off years ago because of 2 cam failures in a week, most likely something i did, but they left a bad taste in my mouth, Ive used them since and have had no problems with the cams

Tim, are those Advanced Marine valve covers? Got a pic of the top of that finished engine?

If it's still apart, check with Danny Griffin at Cam Motion about that RH roller cam. He offered one to me at ~$550.

I talked to him back at the first of this year. I may have the # wrong.

No pic? I wanted to see the hardware you chose on those VC's.

'Advanced Marine and Developement'

Tim,Greg I have the rest of the chain RR cams awaiting shipping with some other parts,I have more than I need just could not let them go in the scrap bin.

TRBenj wrote: Roger, which cams are those? Im confused!

Me too. Did we miss the story line?

Roger, roller or FT?

Ahh, I see. Our "new" vc's are set up essentially the same as the originals in regards to plumbing. There is only one fill cap, located towards the front (high) stbd side. Not sure how large it is- its threaded right into the VC. Each one has a 1.25" hole right in the center (lengthwise), towards the top (middle of the engine), if that makes sense. The 2 grommets are different- one has an ID to match a PCV, the other is for the breather elbow. These holes were cut in the VC's before we got them, but they worked perfectly for us.

I believe mine were probably blank at one point. The 2 holes (breather/PCV) sure look to be custom cut after the fact. The fill may have been there from whoever made them. Only one VC has a fill.

Nice find sir. My gear drive is fine for now, but one of those would be nice for next time.   

Not coming from any direct cam experience mind you, but I would expect that the case hardness is a bit less of an issue with a roller lifter on a steel cam blank than it is with a flat tappet on a cast blank... I never seem to know what is going on with roger these days sounds like a florida sit down is in order.   

Good info Roger- I assume Gen 5 and Gen 6 cams interchange with Mark IV's?

Will be good to finally meet you next month!

I suppose its time for this thread's yearly update... and hopefully the last!

After thinking it over all winter, this spring we decided to go forward with the most reliable (and most expensive, ha) option- custom RH roller cam conversion. The goal was to not tear this engine apart again anytime soon! We worked with Bob Madera at Marine Kinetics (Rochester, NY) on the grind specs and ended up with a wilder cam than before. Due to our engine's high-ish compression ratio, it was decided to go with a longer duration in order to keep cylinder pressures down (and thus avoiding damage causing detonation). Combined with the roller's steeper ramp rates, it allowed the lift to be over .600. Output was projected to be in the ~480hp @ 5600 range.

Of course, in order to use the roller cam, we added tie bar roller lifters. The more aggressive profile required upgraded (Isky) valve springs as well. When measuring our heads to see if our valves would work with the new springs, we discovered that the water ingestion from last year's overheat had left a good amount of corrosion around the valve seats... so off came the heads for a full valve job. Went with +.100 Ferrea valves (SS 6000 series intake, Super Alloy- similar to inconel to withstand higher temps- exhaust) on the rebuild. Custom Manton (Series 4 for guideplate use, 3/8" diam, .120 wall) pushrods rounded out the changes.

We fired it for the first time the Friday of the CT mini reunion and promptly put it in the water. Only a few minor glitches thus far (leaky valve covers, wicked dirty neutral on the tranny, leaky secondary bowl after shut down), but the oil has stayed clean and we havent blown it up yet... so Im declaring victory. Dad and I took our first double barefoot run behind it that first day (Im hoping someone has a picture?)

Pic (thanks Morfoot and Chris) and a quick video (thanks Brian) from that weekend:







(Secondary spring needs to be stiffened up... it was right on the verge with that load in the video, hence the in/out.)

So far, performance has been every bit as good as we had hoped for. We still havent found a prop that we cant cavitate in the midrange. Here's what we've run thus far:

Acme 1598 (13x14 3-blade): 62.8mph @ 5700rpm
Acme 430 (13x13 3-blade): 61.9mph @ 6000rpm
Acme 1868 (12.5x14.25 4-blade): 56.4mph @ 5500rpm
Acme 612 (12.5x15.25 3-blade): 61.7mph @ 5500rpm

So far, I like the 612 the best, as the boat seems to cavitate a little less with it. I expect it to speed up a bit with a full tank of gas and a little weight in back as well (which were the conditions the 1598 and 430 were run under)... I dont see why it wouldnt be the fastest prop of the bunch based on the RPM's its running. The 1868, on the other hand, pushes the nose down HARD in the low 50's, which explains its lower top end numbers. All of the props do this to some extent (as do many of the other faster CC's, like Joe's '83, so I think its partially attributed to the steep strut angle), but this prop does it earlier and harder than the others. It appears to be a different style of prop than the Acmes Im used to seeing (its much flatter, so I may refer to it in the future as a "pancake" prop). This is the stock prop on the Excalibur powered SN 200's, so its stern-lifting abilities may have been a positive on a slalom dedicated tug like that. I may still try the 1442 (13x15 3-blade) and 422 (12.5x15.5 4-blade) on the boat, as it doesnt seem to have any problem pulling the larger wheels out of the hole... its more a battle of being judicious with the throttle to keep the cavitation in check. It will hold ~2800rpm for a split second and then get up to 5k as the boat continues to gain speed. Sort of like a snowmobile... but I think it would be a lot quicker if we could find a prop that hooked up.