Firing timing and firing order and firing degrees with EST

[guuben]

I got my Barr longblock year 2013 "mercruiser" 3.0 l head back from machine shop - warped head .010 mm.
I assume it was a result of wrong fire timing.

A) But i am very confused about the distribuetor and how its attached in the block (from Barr Marine)
Wherever I see a video or read about how to set timing the distribuetor and the spark plug wires are all attached the same way but not mine!
My spark plug wire for cyl 1 starts at no 2 cyl as in attached picture for mercruiser 3.0.
Firing order of course is right with 1,3,4,2. But i thought that the distribuetor could only be connected with cyl 1 in TDC in one certain position ..as all others except mine have, strange .

B) When I connect the two white wires together at the distributor the engine will stop. For a second I can connect them and i get the reading of 0 degrees tdc with stroboscope lamp. I have never connected the third wire beside the white ones....my engine is inboard engine and without interrupting switch.
Maybe the third wire must be connected to batt. + when doing the timing procedure when engine is running (I read about this somewhere) but I have been to afraid to damage electrical components.

C) This too confuses me....when disconnecting the white wires and i make very high rpm,s the timing only goes to about 17-18 degrees tdc!
Idle is about 12 and after that it doesnt change much!


If I understand right a warped head, overheating, damaged valves etc is a sum of to mch tdcb, not because a late firing....right or wrong?
Thanks for your assistance.

(Engine runs today very smooth on idle and response well for rpm,s but in long term I want to avoid another engine crashdown because bad timing.)

 

[stikboyy]

The location of spark plug wires on the distributor cap is directly related to how the distributor was installed. It is possible to install the distributor with the rotor pointing at any of the posts on the rotor; its all about knowing where the engine is in relation to where the rotor is. Generally the distributor is installed with #1 at TDC on the compression stroke. I would say if your engine is running smoothly than having the #1 plug wire in that location is the correct location in relation to the timing.

In order to check/adjust the timing you must connect the two white wires together and connect the third wire to 12V+ (only connect this lead to 12V+ AFTER you have started the engine. if the engine stalls DISCONNECT the lead BEFORE starting the engine back up or you will cause damage to the sensor in the distributor)
Timing should be set at 2 degrees ATDC. With the white wires disconnected and the third wire disconnected from 12V+ timing should move to 13-17 degrees BTDC. and at 2400-2800 RPM timing should be at a max advance of 26 degrees BTDC. Timing is controlled by the ignition module in the distributor, so i would lean toward your module being faulty and not giving you full advance.

Your engine damage is also a symptom of a lean fuel condition which would make the engine run hot.
Hopefully this helps you out.

 

[guuben]

The location of spark plug wires on the distributor cap is directly related to how the distributor was installed. It is possible to install the distributor with the rotor pointing at any of the posts on the rotor; its all about knowing where the engine is in relation to where the rotor is. Generally the distributor is installed with #1 at TDC on the compression stroke. I would say if your engine is running smoothly than having the #1 plug wire in that location is the correct location in relation to the timing.

In order to check/adjust the timing you must connect the two white wires together and connect the third wire to 12V+ (only connect this lead to 12V+ AFTER you have started the engine. if the engine stalls DISCONNECT the lead BEFORE starting the engine back up or you will cause damage to the sensor in the distributor)
Timing should be set at 2 degrees ATDC. With the white wires disconnected and the third wire disconnected from 12V+ timing should move to 13-17 degrees BTDC. and at 2400-2800 RPM timing should be at a max advance of 26 degrees BTDC. Timing is controlled by the ignition module in the distributor, so i would lean toward your module being faulty and not giving you full advance.

Your engine damage is also a symptom of a lean fuel condition which would make the engine run hot.
Hopefully this helps you out.

Hi Stikboyy.

Thank you for your crystalclear answers and info and especially that You pointed specifically 2 degrees atdc (I have it on 1 degrees btdc).
i will connect today the third wire to batt + today and i assume that the engine will not stall now under test.
But as you point out, it looks most likely that I have to replace the electronic timing sensor component in the distributor - broken already as new!


"..lean fuel condition.." : Isnt that only changeable with main jet? The (one and only) fuel/airscrew outside carburetor is only for idle rpms or is it working in high rpms too ?....i must test that.
Colour of sparkplugs was fine until damage...though it isnt so easy to make conclusions these days anymore on sparkplugs to solve out if engine going rich or lean.

Engine goes hot on to much of btdc ...not on to late btdc. Isn't that right?

 

[Bondo]

"..lean fuel condition.." : Isnt that only changeable with main jet? The (one and only) fuel/airscrew outside carburetor is only for idle rpms or is it working in high rpms too ?....i must test that.

Ayuh,.... Poor quality or contaminated fuel is the most likely cause of a lean condition,.....

 

[stikboyy]

"..lean fuel condition.." : Isnt that only changeable with main jet? The (one and only) fuel/airscrew outside carburetor is only for idle rpms or is it working in high rpms too ?....i must test that.

Engine goes hot on to much of btdc ...not on to late btdc. Isn't that right?

On top of what bondo said a partially plugged main jet could also cause a lean running condition.
Advanced timing(too far BTDC) will cause the engine to run hotter; you're right.

 

[guuben]

Yesterday engine runs like a swiss watch....very smooth from 550 to high rpms. No problemas.
Today i got the same disaster as before;
After a very short ride and back to boathouse: restarting just for a check....water in the cylinders....much worse than before.
before it was maybe a tablespoon in cylinder no 3 but now the water came out from sparkplugholes like a firefighters hose when cranking.
( I could not crank the engine...therefore out with the sparkplugs for check)
I suppose i have a warped head again because hydrolock.....but for shure warped not this time either from overheating...my hand was almost all the time on block and thermostat checked...opens at 60-63 degrees celsius.
Before water "only" in cyl no 3...now water came out from all cylinders (sparkplugs disconnected)
Maybe its better to avoid a Don Quijote syndrom and give up. The engine has been a problem for me from start.

Delco est is not changing rpms enough..only to 16 degrees with high rpms.
I connected the"third" wire to battery plus....non help of that either.
Maybe the rawwater pump in front of crankshaft is no good for est !! ??
This i tested before the engines"blow out".

Thanks goes to Bondo too for advice about fuel but i have not elder gasoline in the tank than 3-weeks and gasoline is not stored by me (from gasoline station to tank)

Maybe maybe maybe, I touch the engine tomorrow monday and look whats inside ...with gloves...I dont want to be contaminated ;-)

Money for gaskets (cylinder and manifold) and cylinder head job was just a waste of money....that hurts.

Maybe best to look on the bright side...I still have the new starter for 230 euro (usd 250) and THAT still works, hurray

 

[guuben]

NB, I did a compression test after first start and idle run...a couple of minutes...all between 165 and 175 PSI.

 

[Scott Danforth]

there are more common places that the water may be coming from than a bad head gasket

cracked manifold
cracked head
cracked block
leaking manifold to elbow gasket

I am going to lean toward leaking manifold to elbow gasket as that would fill cylinder 3 quickly.

 

[guuben]

there are more common places that the water may be coming from than a bad head gasket

cracked manifold
cracked head
cracked block
leaking manifold to elbow gasket

I am going to lean toward leaking manifold to elbow gasket as that would fill cylinder 3 quickly.

Thanks Scott Danforth.
I replaced all gaskets with new ones. Head, manifold, elbow, waterpump. All head bolts where sealed, head was tightened in tree steps to 90 f lbs.

This total waterfountain from all sparkplugs was maybe (?) a result from trying to set the Delco Est and engine stopped many times....this idea came to my head today.
Why this thought? ::::::
I have a very long exhaust hose (partly waterfilled 15 feet) and when engine didnt run and there where no real firing combustion the big high capacity waterpump pumped out to the exhaust more and more water and filled it total and in goes through exhaust valves water.

When engine runs normaly the exhaust gases push out the water from the exhaust hose but not this time..doesnt this sound like a logical explanation?
I think many see my engine as a in-outboard motor...but it is a inboard motor and not so suitable as inboard...that I have realized now

And I want to point out today that the exhaust hose was filled up almost to elbow with water when i dissambled the hose from engine.
My very very last attempt will be in boathouse on the floor and IF I get the engine running again without dissambling everything I will have no hose connection from elbow for further"experiments"
First step will be without any coolant water for 5 minutes (waterpump will only pump water but not to engine.
Next step will be with coolant water and out to air from elbow....run it semihot and wait for 15 minutes and then restart (Its always at this point the problems has started in the boat.
.
Engine is now removed from boat anyway.

PS...I could not at all understand how in earth so much water came out from sparkplug holes (if it was from cracked head, manifold or block) ...every compression spitted out lot of water and for many many combustions.....it was like a never ending disaster. First, second....thenth compression stroke for each cylinder spitted out as much as first stroke. It was like a coffecup
for every stroke for each one cylinder.

I think there is still some hope .....but so I thought already many times

I am very greatful for your further comments.
And, do you think hydrolock can warp a semiwarm head, almost cold really.

 

[Scott Danforth]

15' is way too long of a hose

motors naturally have reversion (inhale on the exhaust stroke) at low rpm's. your installation simply is wrong


what is the angle of your exhaust hose? too shallow of an angle and you may as well scrap the motor now. with a 15' hose, your angle should be about 30 degrees.

what is the rise above the water line to the elbow on the manifold. Minimum height is 13", this value increases as your exhaust hose run gets longer

your methods will burn up the exhaust flapper and rubber exhaust hose. fix your installation issues. you may need to add 6 or 9" of riser to your elbow for your installation.

and no, hydrolock simply bends connecting rods and busts pistons before it warps a head.

 

[guuben]

Yes, I think you are absolutly right (problem is the exhaust) though I have elbow well more than 13" to waterline and almost straight downward pointing exhaust hose from elbow..
I think there has never been problem with my "mercruiser" engine...problem was the exhaust....i fully agree on that and that was my hypotethical conclusion from the very beginning.
In another thread it was told to me that there is no way that from elbow/exhaust goes water into cylinder....like it was theoretical impossible.
Theory and practice not always goes hand in hand
My mistake was that i belived that statement....of course it was given in well meant.

Last ten years the boat had two different diesel...first a small mitsubishi 23 hp and then the BMW 45 hp diesel. Never any problem with anything and never water in the cylinders.
Strange that the diesel dont get this hydrolock....can you explain that

There is a lot of sterndrives mercruisers working well but as inboard it is not recommended for anyone.

I put yesterday the BMW diesel back to the boat ...it started after some cranks only and everything worked well except i had problems to stop it..haha....the stop-knob didnt send signal to engine fuel stopsensor.


Tomorrow i try to get the mercruiser to run again.

Maybe the mercruiaer will work with a 15 feet long exhaust hose but the innerdiameter must be relative small...1"-1,5" inch...maybe!
My travel rpm with mercruiaer has always been 1600-1700rpm...occasianly full gas for 10 sec...just for fun

Best regards Henrik

 

[Scott Danforth]

your exhaust tube diameter will be 3" minimum

if your manifold to elbow gasket is bad, it will indeed fill the cylinders with water

hydrolocking is when there is water in the cylinder and you try to crank the motor with the plugs in it. it locks up the motor hydraulicaly. most cases, this will bend connecting rods and crack cast pistons.

 

[guuben]

Hi again Scott.
After first hydrolock i measured gap of each piston up to block top...exactly same distance for all 4 (rod check)
Pistons ok too.
No crack in block or manifold or elbow or bad gaskets.

The test for cracks was made by advice from local finnish machineshop (with very good reputation) but in different way than "standard with aceton".
I think this advice/info is good to share here in Iboats.com. (excellent forum by the way)

Dont use aceton to look for cracks! Use diesel fuel !

If you can make the test in a room what have 24 degrees celsius (75 FH) or more, diesel has less surface tension than aceton.
Aceton vaporize fast, diesel dont!
E.g if you suspect a crack in a cylinder(s) fill the block water chambers with diesel and you will notice and feel very easy if diesel comes into cylinder and if you didnt have messy oil (water) then most likely block is ok.
___________
Somebody else who have a theory why diesel engines dont get this hydrolocks when same exhaust hose is used?
Of curiousity I checked yesterday how much water there was in exhaust hose after testing BMW diesel...only very little at the bottom line of the hose!


Cheers
Henrik

 

[Scott Danforth]

you pressure test the block to look for cracks in the block.

however with a 3.0, if you suspect a crack, toss it, and get one out of the next free rotten boat on craigslist

 

[guuben]

Maybe this question is to odd for this forum but I repeat it anyway one more time.
Does a rawwater pump attached to the harmonic balancer defect EST timing?

 

[Bondo]

Does a rawwater pump attached to the harmonic balancer defect EST timing?

Nope,...