350 sputtering under load.

This was the first head of bolted on since probably high school. Back then re-torque was standard procedure. So I was surprised when the instructions for my head gasket specifically said NOT to re-torque. Fel-pro marine perma torque gasket. I have about six hours on the motor. Should I torque?
 
You shouldn't need all valved done. Just that one. It's usually the exhaust valve that gets hot enuff to punch in the seat (sucking a valve). Intake valve job wouldn't change the compression enuff to warrant a complete valve job. You listen to mechanics that probably have done work on used up engine and compression is all over the place.

Most of the time, setting valves wrong usually makes them looser rather than tighter. Too tight valves will burn them but too loose valves will lower power.

I still vote for plug wires out of order. It's the easiest to screw up and will cause your symptoms. A plug firing at the wrong time can very well blow hot fuel/air out an opening or closing valve. It can also allow a full compression stroke of fuel and air to exit on the exhaust stroke and get ignited by the next correctly fired exhaust stroke. You get big bangs in the exhaust system.
 
Oh, and those perma-torque gaskets are pretty good. I haven't needed to re-torque any of the last dozen or so engines I've built/re-built.
 
Might actually get a chance to work on the boat this weekend; man this summer flew by. Will be replacing the cap, rotor, plug wires, and confirming they are in the right order. Sandy made a comment that has we wondering if I got the timing wrong.

I have the Delco EST ignition, and I don't have the 'shunt' that is supposed to be used drop it into timing mode. If I set the total to 29 at 4k, is that good enough, or do I need to find or fabricate a shunt to set the base timing? Last time I set timing was probably 10+ years ago, and I had GVP on the phone while I did it.I think he told me to set the total, and not worry about the idle. If I'm setting it at total, I don't need to worry about dropping into into timing mode, right? Or did he tell me to set it at idle and not worry about total?
 
Does this engine have roller lifters, or standard hydraulic lifters? I ask, because valve adjustment procedure might be different?
 
Electronic ignition systems are different cuz some ECM do just that...control the timing advance. You'll have to read up on the RPM/advance parameters and exactly where the advance has reached it's total advance.

On the older points with mechanical advance type distributor, the advance is usually all in by 3000 RPM. We had that big discussion back then. Set the total advance of 28* at 3000 RPM for 87 octane. 30* at 3000 RPM for 89 octane and 32* at 3000 RPM for 91 octane.

A mechanical advance distributor may have anything from 12* to 22*. Setting advance for 30* at 3000 RPM with mechanical advance of 22* will end up with 8* advance at idle. 30* minus 22* gives you the 8* for idle. On the other hand, if the mechanical advance happens to be 12* or even 10*, the idle advance will be 18* or 20* respectively. That doesn't hurt the engine at all to have 20* advance at idle. In fact, Keith will tell you, vortec heads love that higher advance at idle. Higher idle advance makes the engine more responsive.
 
My Delco EST is all electronic advance/ignition , and all the documentation I can find( Seloc mercursier book moslty) says to set it at idle, with the jumper in, to 1 degree BTDC - pull the jumper out, it should advance to 11 at idle, and 29 at 4,000 rpm. Since I don't have the jumper, i thought WTF, just set it at 11 at idle - of course that did not work real well, because you can spin the dizzy around pretty good, and the ECM will nail it back towards 11. My next plan was to set it at 29 at 4,000 - again without the jumper. Trying to figure out if that is a valid plan.

In the meantime, the guy at the local auto parts store was able to find me a plug that fits into this socket on the ignition module. Only problem is that this plug has four wires, while it looks like the merc part ( 84-817374A01) has only three. So now I'm not sure which two to connect to each other, which one to the battery, and which one to leave free - assuming of course my module is the same as the Delco module we used at the auto parts store as our template (D1943A) . Not 100% sure if this plug will work, as the store's website lists it as a power window pigtail connector.

None of the online diagrams I've seen so far are clear enough to figure this out. I can order the merc part, and have it by middle of next week - but seeing this is likely the second to last weekend of my abbreviated season, hate to let this one slip by.
 
Yeah, that's tuff. All I saw were the 4 cylinder models. Do you have directions at all? Could it be that you're actually running with the jumper hooked up? That would limit performance. I dug up an old voyager ignition I got on Ebay. Did't work so I stashed it in a corner. Just dug it out. Looks like I made a jumper but unless I see the actual connections or directions, I wouldn't be sure what's what. My guess is, of the two plug ins on the distributor, The one on the right plug are just connected/jumped...but I need a diagram to verify the other plugs connections for the right side.
 
Another thing, how long have you had the delco EST? Has it ever worked right?

I've seen two sets of instructions stating the same thing. If you connect something before you fire it up 'OR' if you connect after you fire it up, it will burn out the ECM. Mine didn't work so I guess I either burned it out or I bought it burned out. Either way, I went back to the TBIV ignition which was working fine even before trying out the delco voyager.
 
Yeah, the delco worked OK before I started on the head replacement. I did run it for several minutes on seven cylinders after the rusted plug shot out, not sure if that may have fried it. I do now know that it was NOT plug wires in the wrong order; although sure wish it was. The new cap and rotor is on, Ill mess with the timing a bit tomorrow- probably not going to put the jumper into the module.
 
IMO, timing would not cause the issues you have (popping). I would sooner think if fuel has no water in it, and supply is adequate, then valve adjustment might be the problem? How did you adjust the valves, what procedure did you use?
 
I think I had the valves right, but since they alternate in these blocks, I thought maybe I botched it, do I readjusted last night , as per the seloc manual, ( tdc, adjust a few , full rev to put six at tdc, adjust the rest. ) took her out for a cruise this morning, and timed it at 28 btdc at 4000 Rpm.

The good news is that I was able to get on plane, and broke the 20 knot barrier for the first time in 14 months. Bad news is that the shaft packing now leak like you wouldn't believe, combined with 42 year old bilge pump that picked today to konk out on me. Off to the parts store. Thanks again everyone for your generous and frequent input!
 
I'm "old school" I like to adjust them with the engine warmed up, & idling. It is the most accurate way, plus you can see the approx. lift on each valve, and if the cam is quite worn, you'll see very little lift, it will be obvious, and it can cause popping out the intake, or the exhaust. Or, if they are not adjusted right that can cause this as well. The book may say to take them down one turn from zero lash, I like to set them 1/2 a turn down from zero lash. This way IMO the engine runs a bit more lively, & peppy, plus they still won't loosen up & clack, at this setting. If they are adjusted too tight, the engine can get sluggish, & run hot. That's the main reason for a preload.
 
Do you know how important it is to have your valves set right? It is the heart of your engine. It will never run right if they're not set right, but once set they hold the setting quite well, unless you overrev the engine a lot. This is not usually an issue with boats normally running less then 5000rpm. "Would you let your Doctor do open heart surgery by the book?" No way! Setting the valves "hands on" is the best way! If I had to do it statically, it would get pretty complicated, but valve timing would be dead on! go figure: With #1 on compression stroke set both valves, move the crank in the proper direction (CC wise I believe) 1/4 turn then set both valves on #8, move the crank another 1/4 turn and set #4, another 1/4 turn to set #3, another 1/4 turn (TDC crank mark lined up again here) to set #6, So you see where I'm going here thru the firing order? Continue on with this till you end up after 2 turns at #1 again! (Remember, this is a 4cycle engine, and requires 2 turns of the crank, hence one turn of the cam, for a complete engine cycle!).

This is so much easier, and just as accurate to do with the engine warm, & idling. You can't just do this Willy Nilly, the book is just a guide!
 
quote:
"Would you let your Doctor do open heart surgery by the book?"
Click to expand...


Well generally no, unless of course the patient was already terminally ill with four other conditions, half his family wanted him dead, and the real doctors charged 180 bucks and hour and weren't available until September. In that case I might let the free guy with a manual have a go at it! (:

I was relatively happy with how this engine ran on Saturday; this is a 42 year old 12,000 pound boat with rusty and tired small blocks - so I typically don't run it more than a few minutes per year over 3,000 rpms - and besides the two and from winter storage trips, we rarely leave the no wake zones.

Is the 'two stop' valve adjustment that bad, with hydraulic roller lifters? I didn't really consider this a willy nilly approach, want to get it right, but not thrilled about taking a third attempt at it.
 
I must have done this procedure maybe 50 times in my life. Sputtering, & backfiring in the intake manifold is a one sign of possibly a camshaft losing it's lobes (going flat) on a SBChevy. I know, I've been there. You'd never know for sure, unless you had the valve covers off while idling to see the lift on each valve.I never heard of a "2 step" method of valve adjustment. How can you be sure that all the valves are closed, and at TDC with a 2 step method? I don't trust a Seloc manual from what I've heard about them anyway. This is your boat, and it's only a suggestion from afar of my assessment of the symptoms. If this is the case, it won't get any better, and you'll have to do something about it eventually. I wish you good luck, and all the best with it.
Mike
 
I just used the two-step method as described here on Boatered and elsewhere:


Once you are sure that the engine is at #1 TDC the following valves/rockers can be adjusted:

exhaust - #1, #3, #4, #8
intake - #1, #2, #5, #7

Rotate the crank 360 degrees and set the other half of the valves

exhaust - #2, #5, #6, #7
intake - #3, #4, #6, #8
 
That's TDC on the compression stroke. Gotta pull the valve cover and watch the rockers on #1 cylinder as the timing mark on the dampener comes up to TDC.

If you don't get it to TDC on compression stroke, you got it all fooked up.

Another thing, running the engine for just a few minutes a year is so bad for the engine. You will increase the condensation in the block if you don't get the engine HOT, HOT to evaporate any of the water in the oil.

Have you heard of acid building up in the block? This is exactly how it happens. A tiny amount of gas is left in the cylinders after shut-down and eventually leak down past the rings. The condensation mixes with the gas along with the natural blow-by of combustion.

http://www.waynesgarage.com/docs/oil.htm
 
I run it almost every weekend, but if going further than one of the anchorages I can see, I take the other boat. A third as old, only one engine, runs perfect ( knock on wood).

Not sure if it was the new cap and rotor, the new plug wires, setting timing at max advance,a re-adjust on the 8 valves I messed with, or some/all of the above, but it ran fine on Saturday, up to full throttle.
 
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