Replacing Spark Plugs

[cheynessa]

I have a 1974 winner convertable. Inorder to change the spark plugs I had to take the exhaust manifold off. But when I put them back on the boat won't turn over. Any ideas???

 

[RogersJetboat454]

Re: Replacing Spark Plugs

Were the spark plugs you used the same type, and length as the ones you removed?
Did you separate the risers from the manifolds? If you did, what kind of condition was the gasket surfaces between the risers and manifolds?

Have you tried pulling the plugs out, and cranking the engine over to see if any water comes out of the cylinders?

 

[wrench 3]

Re: Replacing Spark Plugs

More questions. What do you mean by "the boat won't turn over", the starter won't crank the engine or the engine won't start up? If there were any ground wires that you took off, did they get reattached? Will the engine turn over by hand? What engine/drive are you working on?
One last thought, why would they design a boat like that!!

 

[Don S]

Re: Replacing Spark Plugs

One last thought, why would they design a boat like that!!

Because marine design engineers don't care about minor stuff like maintenance, I have worked on boats that the engine had to be removed to change starter, do tuneups, and change the impeller in the raw water pump.

Most people cut down sockets to pull spark plugs that are hard to get to, not pull the manifolds.

 

[wrench 3]

Re: Replacing Spark Plugs

It's hard to believe people actually get paid for a design like that. I've had to use a wrench on some of the stringers, but never thought of modifying a socket.

 

[ktbarrentine]

Re: Replacing Spark Plugs

+1 on the modified socket.... Found that out the hard way on my 5.0L. Even after modifying the socket, still have to be careful not to put sideways stress on the plug during tightening which can crack the porcelain.

 

[cecho]

Re: Replacing Spark Plugs

Because marine design engineers don't care about minor stuff like maintenance, I have worked on boats that the engine had to be removed to change starter, do tuneups, and change the impeller in the raw water pump.

Most people cut down sockets to pull spark plugs that are hard to get to, not pull the manifolds.

View attachment 186618

Maybe a swiveled style spark plug socket will get in there?

If not maybe one of these will work:
5 8" Custom Short Spark Plug Socket Headers Exhaust | eBay

Assuming the OP doesn't have the capability to machine a spark plug socket.



I honestly think some of these engineers pull crap like that because they hate their jobs. I want to smack who ever designed some of the dumbest designs I've run into.

 

[Don S]

Re: Replacing Spark Plugs

.

 

[cecho]

Re: Replacing Spark Plugs

ROFL, that one took me a few seconds.

 

[wrench 3]

Re: Replacing Spark Plugs

If not maybe one of these will work:
5 8" Custom Short Spark Plug Socket Headers Exhaust | eBay

All the ones I've run into problems with have been the 13/16" hex.

 

[fossill]

Re: Replacing Spark Plugs

Because marine design engineers don't care about minor stuff like maintenance,

View attachment 186618

It's not only them. How about having to pull the cab on a Ford F250 diesel to upgrade head bolts to studs for the cylinder heads , or dissassemble the engine 100% just to change a valve lifter?
Absolutely o excuse and second rate engineering!!

 

[achris]

Re: Replacing Spark Plugs

I work on ROVs, don't talk to me about poor design and hard to get at stuff!!! How about this... A system with a single 8-core power cable. It carries the 110v from one enclosure to another, where the power supplies are (changes it to +24, +12, +5). Then those DC voltages are carried back to the original enclosure IN THE SAME CABLE!!! If you have a suspect power supply, you can't just pull the cable and test, because that removes the input!!! The 2 enclosures, one has about 30 litres of hydraulic oil in it, so draining that to open it is time-consuming and messy, and the other is a pressure vessel and requires a (time-consuming) vacuum test upon closing..... When you're working to very tight time constrains (one minute of vessel time is costs about $2,000), this is a complete PITA.....

:facepalm: :facepalm: :facepalm:

Chris.....

 

[cecho]

Re: Replacing Spark Plugs

...

 

[wrench 3]

Re: Replacing Spark Plugs

Has any one heard from cheynessa? I hope we didn't scare him off when we hijacked the thread.

 

[achris]

Re: Replacing Spark Plugs

Has any one heard from cheynessa? I hope we didn't scare him off when we hijacked the thread.

I guess he got his answer and is now out somewhere machining down a spark plug socket....

 

[tpenfield]

Re: Replacing Spark Plugs

I have a 1974 winner convertable. Inorder to change the spark plugs I had to take the exhaust manifold off. But when I put them back on the boat won't turn over. Any ideas???

Back on topic . . .

My idea about the engine not turning over is . . . did you drain down the manifolds before you took the risers/elbows off? If not, water got into the cylinders maybe :noidea: