1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Is that a 2 barrel carb that we were seeing on this motor???

So, as long as we are ordering parts maybe a 4 bbl carb and a new intake manifold?

If I did that what would it do for me? Other than use more fuel lol Im guessing a bit more hp?

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

The same argument could be made for your lock nut theory. How does it go bad just by sitting over the winter? If you put a socket on the nut and back it off, and notice it has resistance, I would say your lock nut isn't the issue.

Perhaps that lobe on the cam had the valve open all winter, and its lifter bled down, and has not recovered.

As far as an ignition kit, this would be your best bang for your buck deal;
http://www.michiganmotorz.com/delco-voyager-marine-electronic-distributor-p-119.html

I agree about it being wierd to go bad just sitting over the winter. Would the lifter recover on its own? I was going to work on it yesterday evening but was porring down rain last night Im hopping it will stop by this afternoon so I can finally get back to it. Thanks so much for the link for the ignition kit I think I will go ahead and order that sometime this week. $339 isnt bad for peice of mind. I will post an update a little bit later today as to where I am with the tap ect. I also agree with the statement that the auto distributor has prolly been on there quite a while after looking at the wires and cap again. didnt really think about it when i was messing with it lol try to fix one thing at a time i guess. On another note when i purchased the boat the guy told me they rebuilt the lower unit at the begining of last season to the tune of $2200 even showed me a recipt. As far as that goes should i still pull lower unit and check gimble berring and water pump/impeller?

 

[joewithaboat]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Don't overlook what these guys are saying about checking other components for being "marine". Ive been a passenger on a boat that caught fire, burned to the water line and sank. After the 2 fire extinguishers ran out, we all jumped and swam for shore. NOT FUN. It started in the bilge.

Good luck, I'm voting on your trouble being that the cam is going flat or you had a little trash in the lifter keeping it from pumping up.
If you have a flat tappet, not a roller cam, make sure you are using motor oil that has proper anti scuff components for a flat tappet. Most oil today does not, as flat tappets haven't been used in over 10 years in most cases.
Good luck!

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Well guys I broke down and ordered the new ignition system today. Hopefully it will be in soon ... sorry for not posting anything lately on the issues at hand just been completely swamped with work and unable to do anything else with the boat. But I have sloted some time to work on it this weekend will post updates soon.

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

new video's
http://www.youtube.com/watch?v=wTaC...DvjVQa1PpcFP_th3NDXbUv2BafKG1uAx8L3eutfV_jhE=
durring valve adjustment
http://www.youtube.com/watch?v=pnyc...DvjVQa1PpcFP_th3NDXbUvwg4ecRSHelLt5LLWQOIQbU=
after adjustment and everything put back together
http://www.youtube.com/watch?v=pnyc...DvjVQa1PpcFP_th3NDXbUvwg4ecRSHelLt5LLWQOIQbU=
Boat put back together and running
also I have the pictures that you requsted don and will upload them asap

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

 

[Don S]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

That thing sound like .sheet and I can't tell anything from itty bitty pictures.

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

lmao sounds like what don? yeah sorry about the small pictures i will try to get them enlarged sometime tomorrow or later this evening. I did count the threads and they are all the same now and no tapping none of the studs are pulled out at all. I think after sitting over winter that one lifter just didnt pump back up right away (could be wrong). Any sugestions on installing the new ignition system I bought the one that someone put the link of in this thread should be here tuesday.

 

[Don S]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Sounds terrible. If that was my engine, it would be out of the boat, on a stand and coming apart.

 

[Idlespeedonly]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

After the clicking stopped, how much more did you tighten the nuts?

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Sounds terrible. If that was my engine, it would be out of the boat, on a stand and coming apart.

Yeah im trying to avoid that if at all possible. Would like to at least get through this season before I pull it out. It may just be because it sounded like crap from first start up this year but already sounds better than it did ... lol ... I know its not great but im hoping that the distributor and new ignition system take care of a few of the grimlins. I mean the bottom end dosnt seem to have any abnormal sounds coming from it so im thinking worst case senario I pull heads and have them redone.

Randy,
I tightened about 1/4 to 1/2 a turn after clicking stopped.

 

[joewithaboat]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Coopin

If you dont already know, that engine has aftermarket heads on it. I could see in the 1st video above, the S/R cast into the head. Those are "world products" S/R or S/R torque'r heads. You might look into that, not sure if they use a different spark plug or not.

I noticed the rockers are all set to slightly different heights. With those being an aftermarket head Im going to guess they have never had the seats redone on them. So there is no reason for the valve installed heights to be different from one cylinder to another. Also they have screw in studs so its not from the studs pulling out. So in short you need to run ALL of the valves to Zero lash like you did in the video... But you need to add an additional 1/4 or 1/2 turn to them, after the clicking stops. Do them all the same... 1/4 or 1/2

After doing this if you still have different heights, you need to take a look at the cam, might be going flat if its not a roller.

Next thing is... there is usually more oil coming from the rockers while running with the valve cover off. Could be several things there but i would look into that. What kind, weight, of oil are you running. Check the insides of a few of the push rods for build up, the heads look clean but they could be much newer than everything else. A really dirty engine can have low oil delivery to the top end. Could have a really dirty pick up screen.

Oh and by the way, engine needs to be at operating temp when setting the valves. Very important!

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Joe,

No i didnt realize they were aftermarket heads. How would i find out if they use a different plug or not. I will go back and set all of the valve lash on both sides and see where i am this week. I did however count the treads on each with my thumb nail and were all basically the same give or take a lil bit. Yeah i was kind of wondering about the lack of oil coming from them but the engine was deffinately close to operating temperature (well ran it for about 10-15 min before i started adjusting). All the irritation this thing is causeing me im half tempted to just buy a remaned motor and drop it in and say the h*** with it. If only i had unlimited funds

 

[joewithaboat]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Joe,

No i didnt realize they were aftermarket heads. How would i find out if they use a different plug or not. I will go back and set all of the valve lash on both sides and see where i am this week. I did however count the treads on each with my thumb nail and were all basically the same give or take a lil bit. Yeah i was kind of wondering about the lack of oil coming from them but the engine was deffinately close to operating temperature (well ran it for about 10-15 min before i started adjusting). All the irritation this thing is causeing me im half tempted to just buy a remaned motor and drop it in and say the h*** with it. If only i had unlimited funds

By the way they are good heads.

What about the oil type ????, flat tappet or roller?

Their web sight says... Spark Plug: 14mm 5/8" .460" reach tapered style. Accel 276 or 276S or equivalent

web site, should be one of the first two... http://www.worldcastings.com/products/cylinder-heads/small-block-chevrolet-heads/

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Yeah im still new to this stuff. I just put in fresh 25w-40 merc oil which was recomended (expensive crap). what do you mean by flat tappet or roller? I just put in some ac delco MR43T's last week (19157985). Had some old autolights in it before that looked horrible. quite a bit of carbon build up on a few of them. What do you recomend as far as the heads go should i try adjusting the valve lash again or just go ahead and pull them and take them to the machine shop?

 

[joewithaboat]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Yeah im still new to this stuff. I just put in fresh 25w-40 merc oil which was recomended (expensive crap). what do you mean by flat tappet or roller? I just put in some ac delco MR43T's last week (19157985). Had some old autolights in it before that looked horrible. quite a bit of carbon build up on a few of them. What do you recomend as far as the heads go should i try adjusting the valve lash again or just go ahead and pull them and take them to the machine shop?

Oil should be OK

Flat tappet or roller refers to the lifter/cam type.

The plugs you used, although proper for the original heads, don't cross reference with the ones world products recommends. Tapered seat and tread is good, probably a different length. I would buy one of the following and compare them. What was in your heads originally.
look here

http://www.sparkplug-crossreference.com/convert/ACCEL/276S/

the ngk ur4 should be easy to find.

I would run to operating temp and adjust the valves with it running like you showed in the video only add 1/4 to 1/2 turn after clicking stops.
I haven't seen any reason to tear into it yet. Get the right plugs and get the valves set properly first.

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Oil should be OK

Flat tappet or roller refers to the lifter/cam type.

The plugs you used, although proper for the original heads, don't cross reference with the ones world products recommends. Tapered seat and tread is good, probably a different length. I would buy one of the following and compare them. What was in your heads originally.
look here

http://www.sparkplug-crossreference.com/convert/ACCEL/276S/

the ngk ur4 should be easy to find.

I would run to operating temp and adjust the valves with it running like you showed in the video only add 1/4 to 1/2 turn after clicking stops.
I haven't seen any reason to tear into it yet. Get the valves set properly first.

The plugs I pulled out were autolight 26's pictures posted i think. I will get new plugs from advanced tomorrow that world products recommends. Should I go ahead and adjust both sides? And should i replace the distributor first or just do it with the one thats currently in it? is 10-15 min of run time good enough to get the motor to operating temp? also im not sure which lifters i have how do i tell ... there are some pictures of the lifters posted earlier if that helps.

 

[joewithaboat]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

The plugs I pulled out were autolight 26's pictures posted i think. I will get new plugs from advanced tomorrow that world products recommends. Should I go ahead and adjust both sides? And should i replace the distributor first or just do it with the one thats currently in it? is 10-15 min of run time good enough to get the motor to operating temp? also im not sure which lifters i have how do i tell ... there are some pictures of the lifters posted earlier if that helps.

Get proper plugs

Adjust both sides

Temp gauge should tell you if at operating temp, 15 min should be enough

Pictures are pretty small, looks like you at the very least have a roller ready block.

Easiest way for you to tell now by checking something and reporting back here is a bigger picture or just pull a push-rod and tell us how long it is. This really make no difference in you getting it running well.

Get the actual part number on the head the next time you have the cover off.

Distributor is potentially dangerous, looks like it is not a marine unit. It wont prevent you from setting the valves but i wouldn't take it out on the water.

 

[81 Checkmate]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

coopin - Too me that motor just doesnt sound right. What i would be worried about is no oil coming out of the pushrods.

It should be squirting oil everywhere, especially if the motor had be running for 15 min.

Thats why it is so noisey!

Me personally i would not start it anymore untill i found out why!