96 5.7L Mercruiser - no compression, water in

[96RinkerCaptiva212]

You won't have any problem running a ground wire from the minus tab to any convenient ground nut on the motor. The motor is well grounded.

Is that brass vent into the choke? Might be some sort of convertable heat riser fitting. I have no idea what else it might be. Too low for dumping a failed mechanical fuel pump overflow line...

If you stabbed the disty near TDC, next is to spin it up and set the timing. Can't get it much closer just by eyeballing it. Highlight your marks with chalk or white paint and you can set timing even before the motor starts. Good timing light will fire while you crank letting you nail it down.

1) Choke Fresh Air - found this diagram finally, below. Never mentions anything about hooking something up to it. Surely that thing just doesn't sit open to atmosphere with a metal screen?

2) Maybe I assumed too much with the disty cap. I now see that the previous owner had the #1 contact on the cap, pointing on the opposite of the engine away from #1 cylinder. I thought the rotor needed to be pointing at #1 cylinder on TDC and the #1 contact on the cap would be mating with the rotor (everything pointing to #1 cylinder). Is that not true? I've only had this boat for a year now so I'm not sure what all was done since '96. I can't rotate the cap 180 degrees because of this vent port on it in the 1st pic below. It is hitting the rear harness connection. So at this point, I have #1 cylinder on TDC, so I need to pull disty and drop it in so the rotor is pointing the opposite way, mating with the #1 contact on the cap? The 2nd pic shows a white paint spot on top of the cap for #1, pointing kind of towards bilge pump. This is how it was when I removed it while troubleshooting. Gosh, I'm so close and keep running into little things!! I wish I was more of a gear head!

 

[Rick Stephens]

It matters not at all what is marked as #1. All that matters is that the spark plug wire that goes to the #1 cylinder is lined up to the rotor when the engine is at #1 TDC.

You can crank the engine to #1 TDC, close your eyes and poke the distributor in, then stick the wires on the cap based on where the rotor is pointing at that moment. Normally, you set where #1 is by virtue of the easiest to route the wires. Don't worry about marks on the cap unless you already have all the wires installed, then stab the disty so the rotor points where YOU want it.


Chokes create heat. Having a vent would make some sense. I would ignore it.

 

[96RinkerCaptiva212]

It matters not at all what is marked as #1. All that matters is that the spark plug wire that goes to the #1 cylinder is lined up to the rotor when the engine is at #1 TDC.

You can crank the engine to #1 TDC, close your eyes and poke the distributor in, then stick the wires on the cap based on where the rotor is pointing at that moment. Normally, you set where #1 is by virtue of the easiest to route the wires. Don't worry about marks on the cap unless you already have all the wires installed, then stab the disty so the rotor points where YOU want it.


Chokes create heat. Having a vent would make some sense. I would ignore it.

Ok, going to do that now and I thought that was possible (ignoring numbers on top of cap) as long as everything is on #1 and prepped to fire. Thanks for confirming. So, given the vent tube obstruction on the disty cap, I will go back to the way it was and drop the disty 180 out so it's pointing away from #1 cylinder (top button/spring will be pointing at #1 cylinder). This is actually what made me think the engine jumped time orignally. Wrong again, lol.

Next, timing. Earlier, were you saying I can set the timing by manually turning the crank over instead of starting up? I thought I was at the point of starting up and hitting the timing light for the adjustment for idle timing.

 

[Rick Stephens]

You'll have to crank it to see timing marks and fire the light. However it doesn't need to have started yet. Crank the motor and set the timing at same time.

 

[96RinkerCaptiva212]

You'll have to crank it to see timing marks and fire the light. However it doesn't need to have started yet. Crank the motor and set the timing at same time.

oh, you mean crank the starter, with the plugs out

 

[96RinkerCaptiva212]

I'M ABSOLUTELY SICK TO MY STOMACH.. put a plug in as I had to go get another set since I learned the vortec heads take a longer thread length. Put one in and wanted to rotate the engine over by hand to ensure there was no clearance issue. Crank turned over and pulley did not... *FACEPALM*.. I usually pull a belt while I turn the crank to relieve tension from the torque of the crank bolt. I reached down and now see the crank bolt washer is barely loose. :faint2:

I tried to then back the bolt out to look at the threads and the bolt is turning the engine over in reverse as well. Looks like over 60lbs of torque trying to reverse the bolt out. Absolutely disgusted with myself! :mad-new:

So now, I'm all ready to fire up and set timing and I'm stuck now pulling the engine again. hopefully the bolt will come out and not snap off and have to be drilled out. Hoping I can chase the threads in the crank and get a longer bolt. It would appear I got some bad info off of a camaro forum that said crank is 60lbs. I see it is actually 35 lbs now on the specs. Actually looking now to see if I can just fairly easily remove the back bench seat and raise the engine some to expose the crank. My bad side is saying just idle it and set the timing and watch the crank pulley to see if it's trying to walk any. I mean it was pressed on and it does have 60lbs holding it at this point. My thought is the harmonics may back the bolt off I guess. I think when it was on the stand, I felt the 60lbs snug in and thought it was bottomed out when in fact it was just barely shy. ayiiyiiyii

 

[tpenfield]

So you are saying the bolt on the crankshaft is bottomed out, but not snug, as in the bolt is too long, and now you can't get it to back out because it is over tightened?

:facepalm:

 

[Rick Stephens]

I don't know what to recommend... me being me, I'd put a impact wrench on it and run it off. That's me. I'd then fix whatever I found. Even if I trashed the threads, I figure I could go up a size and drill/tap it out.

tpenfield asked a great question. I didn't think about the bolt being too long. My first thought was the threads got stripped. Bottomed out would be both better and worse. Better if the airgun blew it out without fuss, worse if the bolt end got mushroomed at all.

 

[tpenfield]

I would think if the threads were stripped, the bolt would pry out pretty easily.

It is a fine pitch thread and deep threaded. I would hope it would not have stripped even though over torqued.

 

[Rick Stephens]

I would think if the threads were stripped, the bolt would pry out pretty easily.

It is a fine pitch thread and deep threaded. I would hope it would not have stripped even though over torqued.

Yah to all of that. All said, I would still blow it out of the hole with an impact wrench and see what was what.

 

[96RinkerCaptiva212]

Ok guys - I feel better now. new longer bolt and back in action. It seems the old bolt threads are "shortened". I must have done that when I tried to turn the motor over by hand when #5 was locking up at the top of the stroke with the piston top being damaged. Anyway, moving on.. phewww... #1 is back on TDC compression stroke.

I hooked the muffs up and tried to start it up. Figured it would take quite a few cranks to get the fuel back through the filter/pump and up to the carb. Wasn't firing, I decided to drop a small cap full of gas into the front cab bowls. Cranked and it seemed to halfway backfire. Cranked again and nothing. I pulled the fuel line going into the carb and there is no fuel coming through from the pump. Looks like I've wired the relay/pump power incorrectly somewhere.

I first tested the ground but with the meter set to ohms, I got it read 0.00 when hooked to the end of the ground wire that would go into the negative post of the pump, and touched the stud where I have the ground ring secured (front block stud). I think this means I have good ground.

I then had the wife crank the engine while I had my voltmeter set to direct current. With the red pin in the end of the positive wire for the pump and black pin on the rear engine ground stud (also houses the battery ground), I got no reading other than zero when wife cranked the engine. Hit me that DC is probably not the correct meter setting, i switched it "12V" and tried again, same thing, no 12v reading like expected. Seems this is where the issue lies. Hoping you guys see something below that sticks out as incorrect. FWIW, I do have oil pressure building while I crank. Close to 40 even though it's not firing. I have the rear oil port T'd with oil sender on one side and the pressure switch on the other side. To review my setup:

From Relay:
30 is fused with 10amp and spliced into the purple wire heading into the back of the alternator
87 is going straight to postive post of carter fuel pump
87a is not used, taped it off
86 is going into the "P" on the oil pressure switch
85 is going to the negative terminal on the coil

Starter (new DB unit and is cranking the engine well):
2 reds and orange on the main post
yellow/red wire is on the inner starter post
outer post - i have a wire going from this lug straight to the "S" on the oil pressure switch (one drawing Rick had looks like outer lug goes to battery, but another wire splices from that over to oil pressure switch) Unclear if I messed up here.

Pump:
The positive wire is coming straight from 87. negative post is grounded on stud on front of block

Oil Pressure Switch (3 prong):
"P" is wired to 86 on the relay
"I" I tied into the purple wire on the main harness, before that large black terminal plug
"S" wire comes straight from Starter

 

[Rick Stephens]

Take a wire, hook it to plus and work your way up to the pump. Test the relay - put power to 86, or to the oil pressure switch.

If I leave the boat parked for the winter, I short from bbattery plus cable on the starter solenoid to the outer fuel pump lug till the carburetor is fully primed.

When you crank your engine you can also double check timing.

 

[96RinkerCaptiva212]

Take a wire, hook it to plus and work your way up to the pump. Test the relay - put power to 86, or to the oil pressure switch.

If I leave the boat parked for the winter, I short from bbattery plus cable on the starter solenoid to the outer fuel pump lug till the carburetor is fully primed.

When you crank your engine you can also double check timing.

So I went out in the dark just now and took the wiring setup back to "step 1". Just using the oil pressure switch, I hooked purple up to the ignition terminal, outer starter wire to S termian and then ran the "P" (pump) terminal straight to the pump. I cranked it and as soon as I built oil pressure on the 2nd or 3rd rotation, the fuel spewed. I can see that the pump stays running until you turn the key back off. So, that eliminates the oil pressure switch. The "P" terminal seems a little loose on it so I thought I was dealing with a faulty switch but that's not true. Now I'm back to figuring out what I've done wrong with the relay wiring.

I need to just get my wife out there tomorrow so I can check the timing with the plugs out. I went to try and fire it for a quick sec and it backfired again on me. I pulled all the plugs and then stuck a paper towel in #1 and turned the motor over by hand and 2 revolutions and it didn't push it out. Seems odd... When checking TDC earlier the wife said she felt air on her finger but it didn't "blow her finger off". I am being easy on the crank by hand for obvious reason so I told her as long as she feels the air pushing out, were good. So, can't explain yet why the towel wasn't blowing off. It was pitch black and I'm tired of working on this freaking thing. I'll start with a fresh mind in the morning. I'd like to just get it running and timed with current fuel wiring. After that's tuned in, I'll go back to the relay wiring issue.

Is it normal for a new engine to backfire due to assembly oil? Has to be a timing issue. I'll get it back to TDC tomorrow and recheck the disty so the #1 terminal is matched with the cap contact.

 

[Rick Stephens]

It is not normal to backfire. Your timing is not set right.

Not to pick on you, but all this is why it was recommended that you totally set up your engine out of the boat. Many people will run their motor on blocks before sticking it in. You get the wiring built, the timing set, carb idle set. The whole enchilada. Nuf said, but it really is a LOT easier than doing all this in the boat.

 

[96RinkerCaptiva212]

It is not normal to backfire. Your timing is not set right.

Not to pick on you, but all this is why it was recommended that you totally set up your engine out of the boat. Many people will run their motor on blocks before sticking it in. You get the wiring built, the timing set, carb idle set. The whole enchilada. Nuf said, but it really is a LOT easier than doing all this in the boat.

Point well taken Rick, I'm 35 but my knees are hurting at this point with this mess. I discarded that tip since I'm normally not bothered by crawling around an engine. A boat really changes the game there. I'll kick the motor around with the starter and verify I get back to the compression on #1. I followed the recommended rocker adjustment guide by #1 being on TDC, adjusting that combo of intake/exhaust valves, then rotating to #6 on TDC and doing the same. Several push rods were pretty loose as far as rotating clockwise and counter. I snugged it until the rod was snug and then tightened 1/2 turn (some manuals say 1 full turn for vortec). I'll check the disty and rotor position and make sure all my wires are installed with the firing order. Reading around sounds like I have it advanced too much.

 

[96RinkerCaptiva212]

SUNDAY UPDATE! She is up and running!! Sorry for wearing on everyone, I was getting pretty frustrated these past 2 days.

I started this morning and tore the risers off and rocker covers. The reason why I didn't seem to have compression yesterday is because the rocker nuts were too tight. I was listening to a few posts from SBC car forums and vids that said remove all rotation from the pushrods and this is zero lash. Then tighten to 1/2 to 3/4 of a turn. I also saw the mercruiser manual said one full turn for hydraulic lifters. This must have opened both valves. This morning I looked back over the service manual and noticed it states zero lash as no "up and down" movement of pushrod rather than clockwise/counter-clockwise movement. For now, I left them just right at the point of actual spin rotation. I found at the point of no up and down movement of the pushrod, a full turn as stated in the manual, seems to lock them down again too much. I actually wonder if my drill didn't fully load the lifters when I primed the oil system like I expected it would. With cranking the motor over last night they seemed extra tight. Anyway, motor is running and I'm 99% sure I don't hear any rattling. I can always pull the risers and adjust them more after they get some run.

I set the timing with the plugs out, except #1.. found the timing was super advanced. With it warmed up at idle, I have it at 10 degrees BTDC. I'm doing some research now to see if that is acceptable or not. Not finding it exactly in the manual. I really want to get a paper version of it. At 10 degrees, it's idling at just above 600. Seems like I saw somewhere it needs to be 750 but will verify.

Temp stayed at 160 or dropped a little when t-state opened, oil pressure right on 40psi.

** I still have the fuel pump only wired through the oil pressure switch so I will need to start fresh and figure out what I've done wrong in the wiring. 87 is definitely not delivering 12v to the pump. I'm starting to think I actually need to be using 87a as it says "NC contact" in this diagram that came with the relay. Adding a 3 prong oil switch, it has a common, NC, and NO contact.

 

[96RinkerCaptiva212]

1) Outside of the relay issue, here is what I'm not certain on. Do I have a Thunderbolt IV ignition? See 1st pic below. I don't see a spark module mounted onto the control module so pretty sure it's not a V. This number on the tag doesn't come up with anything. Trying to ensure I'm timing this thing correctly. It seems I don't need to jumper the harness if it is a IV unit. I just went out again and it started right up perfect with only 1 throttle pump. RPM at like 620ish and timing at idle actually looks like 6-8 BTDC. The light seems inconsistent or maybe that's just normal. Jumps between the 2 degrees. Probably the cheap $45 unit from O'Reilly. Is my next step to hold throttle at 3k and check advance? That probably needs done in the water really as I'm sure I can suck the hose closed pulling water like that.

2) Slight concern on temp gauge. This 2nd round of running it went to 160 then 170 for a short bit, then dropped down to 120 or bottomed out on the gauge. I shut the engine off, restarted it and it held around 140-150. My hose was sputtering when I first turned the spigot on so thinking it's just air. You don't really burp these any way do you? I probably just need to watch it on the water and see how it acts.

3) PVC setup. This is my old bracket and wiring loom setup from the last engine in the 2nd pic. I never noticed before but now see the gases just escaping the loom by that hold down bracket. This seems odd to me. Shouldn't the PVC gases be routing somewhere? My old spark arrestor didn't have any ports. This one has a large and small port. Do I hook the 2 PVC valves up to a hose and T them into the large port on the arrestor? Anything I need to do with the small one?

 

[Rick Stephens]

I can't believe that you would blow out any air when you turn on the water to muffs. They aren't that tight of a fit that water doesn't squirt out. Did you install a 140 or 150 thermostat?

There is no PVC, just breather hoses to take any blowby and feed it into the carb for safety reasons.

I have no clue whether that is TIV or T5. Someone smarter than I will have to pop up with an answer. The part number does search out though. Found it ending at A1 on iBoats, #23. Spendy little booger.

 

[96RinkerCaptiva212]

I can't believe that you would blow out any air when you turn on the water to muffs. They aren't that tight of a fit that water doesn't squirt out. Did you install a 140 or 150 thermostat?

There is no PVC, just breather hoses to take any blowby and feed it into the carb for safety reasons.

I have no clue whether that is TIV or T5. Someone smarter than I will have to pop up with an answer. The part number does search out though. Found it ending at A1 on iBoats, #23. Spendy little booger.

I saw the manual said 143 degree. It always operated at 160 before and I see a lot of people run 160 on the 96 and later 5.7's so that's what I have back in there again (sierra unit). I'm not opposed to switching it out to 140. I thought I would take the old t-stat with me to the lake for a backup.

gotcha, I assumed the elbows heading into the grommet on the valve cover was a pvc. I'll start a new topic on the disty and see if anyone has experience.

I'm going to go buy a vac gauge today and pipe it into an intake port to start tuning the carb in. I closed the mixture screws in and backed them out 1 1/2 turns for the base setting, per Holley recommendation. As long as I have the Thunderbolt IV and don't need to do this jumper wire, base timing mode process, I think I'm ready for water! I'm going to just secure the fuel pump wiring as is for the break in with the oil pressure switch setup. Then revisit the relay here in a week.

 

[96RinkerCaptiva212]

Well guys, I just wanted to stop back in and say THANK YOU SO MUCH for all the help!! My wife and I went out for 5 hours on Saturday and another 2 on Sunday and it went nearly perfect. Just a very small water drip on the water pump hose. I didn't tighten it down enough but a 5/16" took care of that. I ran it at 1500 pretty much the whole time and every 45 mins, I did a little rpm run on plane for 2 minutes.. increasing the rpm on each subsequent run. I really couldn't have pulled it together without all the help in this thread!! So thanks again, the wife and I are overjoyed to be back on the water.