Mikentucky
Member
- Jul 31, 2020
- 61
- Boat Info
- 1994 400 Express Cruiser, "Lollygagging"
- Engines
- twin inboard Mercruiser 7.4L Bluewater, straight drives
So about 6 weeks ago we bought our 1994 400EC with Bluewater 7.4 Gen V carbureted motors and Hurth straight drives, right at 975 hours each motor with no major work. Both engines ran good on our sea trial with good oil pressures and temps, and in the weeks since haven't burned any oil or lost coolant. At the sale, we negotiated an agreed-to price that was reduced with the expectation that with 975 hours, engine work would be in our near future...we just didn't know how soon LOL This past weekend we had her out for a Labor Day excursion 60 miles downriver. On the ride back home the port engine lost almost all thrust power (but still good temp and oil pressure and still showing 3k on the tach)...got a little bit of valve clatter and "chugging" for about 15 seconds....then died. No puffs of smoke, no loud bangs, no messes in the bilge, nothing obvious but wouldn't restart. I left the port engine off and came on home under starboard power, all good. I went to the marina and checked on it yesterday--oil and anti-freeze are both still full and clear, good signs. It will start up and idle at about 1100 while rhythmically chugging, anything less and it dies. I pulled both valve covers thinking I maybe had a loose rocker, bent rod, etc...everything on the top end of the heads appears intact, so I'm pretty sure I've spun a rod bearing. This weekend I plan on pulling the plug wires one at a time listening for the chug to go away to confirm.
If so, now there's choices on what to do...I'm a heavy equipment mechanic by trade, used to laying on the ground in the rain or snow to fix heavy, dirty things While I'm comfortable doing a motor rebuild, after 20+ years of "heavy and dirty" I would rather pay somebody to do it if it's not terribly more expensive. That said, I am tentative about uncoupling the Hurth tranny or messing with a propshaft because I'm not sure what to expect. And even though a short or long block might be an obvious choice for some, for me I'm old school--there's just something nostalgic about a vehicle or vessel having the original motors. The owner for the first 20 years was meticulous, I still have all of the original manuals including both engines, all service and sales records, even a copy of the original build sheet and pricing sticker.
Do-it-yourselfers, has anyone done a bottom end rebuild in the bilge of a 400EC? I've got the seats moved and all the hatches off, looks like there's quite a bit of room.
As I'm looking at it, my choices are:
1.) Rebuild just the bottom end of the motor in the bilge--the least expensive route, fixing only what broke. Disconnect things as necessary, leave the heads on, lift it off the mounts and roll it on it's side to do just the crank, pistons, piston rods and bearings, oil pump, etc. But again, this requires me to unhook the engine from the drive/propshaft and I'm not sure if I might tear up something drive related because of my lack of knowledge on a marine drive setup. And with this option, the top end is still 26 years old and original.
2.) Rebuild the whole motor, have the block and heads reconditioned--have a yard disconnect and pull the motor and load it into my pickup, then have them re-install it after I do the rebuild in my garage.
3.) Skip the rebuild and install a short block with my heads and other parts.
4.) Install a long block--the more new parts, the better.
5.) Go with new crate motors, either OEM 7.4's or maybe 8.1 Horizons.
Am I causing more headaches down the road by doing a rebuild--parts hard to find, reliability not as good as a short/long block with marine technology changes? Share your thoughts as well as "do's and dont's" with me, please!
If so, now there's choices on what to do...I'm a heavy equipment mechanic by trade, used to laying on the ground in the rain or snow to fix heavy, dirty things While I'm comfortable doing a motor rebuild, after 20+ years of "heavy and dirty" I would rather pay somebody to do it if it's not terribly more expensive. That said, I am tentative about uncoupling the Hurth tranny or messing with a propshaft because I'm not sure what to expect. And even though a short or long block might be an obvious choice for some, for me I'm old school--there's just something nostalgic about a vehicle or vessel having the original motors. The owner for the first 20 years was meticulous, I still have all of the original manuals including both engines, all service and sales records, even a copy of the original build sheet and pricing sticker.
Do-it-yourselfers, has anyone done a bottom end rebuild in the bilge of a 400EC? I've got the seats moved and all the hatches off, looks like there's quite a bit of room.
As I'm looking at it, my choices are:
1.) Rebuild just the bottom end of the motor in the bilge--the least expensive route, fixing only what broke. Disconnect things as necessary, leave the heads on, lift it off the mounts and roll it on it's side to do just the crank, pistons, piston rods and bearings, oil pump, etc. But again, this requires me to unhook the engine from the drive/propshaft and I'm not sure if I might tear up something drive related because of my lack of knowledge on a marine drive setup. And with this option, the top end is still 26 years old and original.
2.) Rebuild the whole motor, have the block and heads reconditioned--have a yard disconnect and pull the motor and load it into my pickup, then have them re-install it after I do the rebuild in my garage.
3.) Skip the rebuild and install a short block with my heads and other parts.
4.) Install a long block--the more new parts, the better.
5.) Go with new crate motors, either OEM 7.4's or maybe 8.1 Horizons.
Am I causing more headaches down the road by doing a rebuild--parts hard to find, reliability not as good as a short/long block with marine technology changes? Share your thoughts as well as "do's and dont's" with me, please!