1990 rebuilt 5.7 water in oil and timing problem

[stang32]

hey guys i need some help, i am installing a new motor and i have it mounted on a pallet on a trailer for testing purposes, i have the manifolds risers and elbows in place. with water running through the engine. all new exhaust (sierra) and i am getting water in my oil. could the exhaust not being atached to the y pipe be sucking the water back into the cylinders? this is the 2nd time this is happened. the ist time i sent the engine back to the builder, i filled the manifolds with acetone and found no leaks, i had the intake pressure tested and no problems found.
the 2nd issue it the timing. i can not get the timing to within specs and sound right.
this rebuilt engine has a pertronix ignition in a pretrolte dist.
the engine idles the best at 22deg btdc, when i bring it to 8 deg, it runs rougher, not as smooth as 22. the vacuum gauge is very bouncy, violently bouncing from 16-22i in hg.
i have confirmed tdc with a tdc locator and it lines up with the timing marks perfectly. what am i missing? i have never had an issue like this before and i am stumped
the engine has already been back to the builders and they claim there is no issue what so ever with it. so how do i explain the vacuum gauge dance and the timing issue?

if the water in the oil is caused by the manifold back pressure, whats the fix for that?

i know the truck cams have an overlap in the valves which could cause ewater to be sucked in so what to do?
i hope i can get some answers on this , thanks guys

 

[kenny nunez]

With a unsteady vacuum gauge it appears a valve is either not set right or an intake valve is not opening at all which will draw water back into a cylinder. You may have a rounded cam lobe. Is there any water getting on any of the spark plugs.
Put 20-30 lbs of compressed air in the engine to see if there are any pin holes in the casting and with the spark plugs out listen for escaping air.

 

[Scott Danforth]

lets educate you on marine motors, too much base timing and reversion. a lesson I learned the hard way

anything over 14 degrees of advance on an SBC with a stock cam and you will start to suck water in the manifolds from the exhaust. at 22 degrees advance, at every cylinder firing, you will see the wave front reversion with your naked eye.

at 22 degrees of base timing to get it to run, you have an other issue - most likely your not adjusted correctly with the valve lash. that erratic vacuum is indicating a dead cylinder

what cam are you running? post the cam card specs
what carb are you running?

first, change your oil
next - verify your valve lash
then do a compression test
after that, set the timing to between 8 and 10 BTDC
then run your motor.

 

[Scott Danforth]

one issue, if the timing is off a tooth, you would have to run the motor that far advanced. was the cam degreed?

 

[stang32]

one issue, if the timing is off a tooth, you would have to run the motor that far advanced. was the cam degreed?

please explain to me how a distributor being off 1 tooth can have any effect on how it runs when you have to set the timing by moving the distributor any way? be ause i have had this discussion for about 35 years now.

 

[stang32]

lets educate you on marine motors, too much base timing and reversion. a lesson I learned the hard way

anything over 14 degrees of advance on an SBC with a stock cam and you will start to suck water in the manifolds from the exhaust. at 22 degrees advance, at every cylinder firing, you will see the wave front reversion with your naked eye.

at 22 degrees of base timing to get it to run, you have an other issue - most likely your not adjusted correctly with the valve lash. that erratic vacuum is indicating a dead cylinder

what cam are you running? post the cam card specs
what carb are you running?

first, change your oil
next - verify your valve lash
then do a compression test
after that, set the timing to between 8 and 10 BTDC
then run your motor.

this is totally new news to me, please can you explain this further? i have never heard this.
the engine was rebuilt using standard parts, no hipo, no degreeing the cam, just a standard marine engine kit. again, i can only assume, this rebuilder knows what he is doing. he made a point of telling me about 5 times that "I REBUILD 30 5.7 SBC MARINE ENGINES A WEEK HERE, BLAH BLAH BLAH BLAH BLAH...."

it is running a quadrajet.,

 

[stang32]

here is a link to the engine running, 1st @ 23 degrees btdc, the second running @ 8 degrees

https://photos.app.goo.gl/BWHvfZxF6sxCq7Hf8


the vacuum gauge does not appear ot be bouncing as much as it does in real time due to the whole video thing but trust me the needle bounces so fast you cant even read it some times

 

[stang32]

before i put the timing cover on, i verified the 2 sprockets linrd up perfectly and the #1 cylinder was at tdc

 

[stang32]

ok, so i just read up on reversion, which it turns out, i do know about, just didn't know the term,

 

[Scott Danforth]

wasnt talking dizz being off, talking the cam to crank relationship

doesnt matter if you lined up the marks. I have had cams that had to be installed 2 degrees off to be "straight up" once you degree the cam. if the cam wasnt degreed, you dont know what you have. every good engine builder will degree the cam as part of normal assembly.

with advanced base timing, you create more vacuum at idle, which, leads to more reversion at idle.

also, where are you taking your vacuum from? if your taking it from the plenum you will get a different reading than you get taking it from the one runner that has a pipe plug in it. you get more pulsing taking it from the runner

 

[stang32]

there is only 1 area on a sbc manifold to take vac readings from , yes the runner with the pipe plug in it

 

[stang32]

lets educate you on marine motors, too much base timing and reversion. a lesson I learned the hard way

anything over 14 degrees of advance on an SBC with a stock cam and you will start to suck water in the manifolds from the exhaust. at 22 degrees advance, at every cylinder firing, you will see the wave front reversion with your naked eye.

at 22 degrees of base timing to get it to run, you have an other issue - most likely your not adjusted correctly with the valve lash. that erratic vacuum is indicating a dead cylinder

what cam are you running? post the cam card specs
what carb are you running?

first, change your oil
next - verify your valve lash
then do a compression test
after that, set the timing to between 8 and 10 BTDC
then run your motor.

scott, i am still chasing ghosts on the motor. the timing is now at 8* and it is running ok, i changed the oil 3 times, to get the oil looking clean. i scopped the manifolds through the top 1/4" plug on the riser(elbow) and i can see water trace marks running down the inside of the ,riser, spacer and into the 2 center ports of the manifolds. i can see the top of the risers is wet where the risers go from verticle to horizontal over the hump.
is it common for a little water to be entering the manifolds when running at idle due to the suck push of the exhust valves or is there stil a problem which i will need to further address?

in the photos below you can see the water track marks as well as the tiny puddle at hte bottom of the center 3 manifold ports.

https://photos.app.goo.gl/5KznTELpvtczCD9s9

photos 1& 2 show puddles or drops of water on the bottom of the manifolds,
3 & 5 show the trace of water coming from the top section
& 4 shows the bend of the riser from were it goes from verticle to horizontal.
both manifolds look like this.
is this SOP?

 

[Scott Danforth]

at 8 degrees you should not have reversion

reversion is more of a mist and less of a trickling stream like you have shown.

what brand of elbows are you running?

have you done an acetone test of your elbows?

 

[stang32]

i have sierra manifolds and elbow, with barr spacers. yes i did the acetone test. last week i put long bolts on the manifolds and pulled them about 4" away from the heads, i had the water running through the manifolds using a garden hose without the engine running. the upper riser hoses and the engine block to manifold hose has been plugged. the manifold is being fed water through the lower hose on the manifolds. after running the water for several minutes i saw water seeping from the 2 center exhaust ports on each manifold.after draining the manifolds, i broke the manifolds down, removing the risers, then spacers, i can see a puddle in each of the center ports of the manifolds. the gaskets look fine, although they are destroyed now, they were not blown out, off set, cut, torn etc...
the manifolds are leaking from 1 of the 3 sections.. i am so tired of spending good money and getting garbage parts. now i have to take all the pieces to a machine shop and have them plane the decks, put them all back together with new gaskets and re-test them all over again.
i called sierra today and he cant give me any reason why water would be entering. he says it should not be happening.

yesterday i had a machine shop plane the surfaces true and flat. i reassembled them with quicksilver gaskets from merc. i have an endoscope i sent down the riser through the 3/8" plugged hole on top of the riser and i see the water entering through the outlet hole of the exhaust, the large center hole. is this normal operation. i

please can anyone agree or disagree that there will always be a slight amount of water entering the manifolds when it is running due to the suck/blow action of the exhaust valves?

 

[NHGuy]

First off double check that your ignition wiring contact are super clean and shiny. Battery must be fully charged.

I have personally seen sketchy ignition contacts cause poor running. Which in turn caused me to advance my timing. I had a vibrating vacuum reading while I was running then too. After I repaired that stuff I tested my vacuum (good) with a different gauge so I'm not sure if it was the gauge or the electrical problems, but I have my suspicions.



Were you seeing water entering while the engine was running? Or just while running water alone? If you were running water without the engine running were the exhaust hoses on there, or were the risers open at their ends? Were they sloped away from the engine?

If water isn't entering the exhaust stream in the manifolds, risers, or elbows you should be good. Run the motor at 8 degrees btdc. Then shut it off and check for water in the exhaust manifolds and on the spark plugs.

I have a 1997 350 Mag with new factory Mercruiser manifolds and tall risers on a stand in my garage. The previous owner of my boat had them put on just before I bought it. I just went out and looked at it.
The Mercruiser risers 3/8" plug goes into the exhaust. You can look down it right into the manifold.
Water from the cooling system is released at the back of the riser at the top. So if your exhaust isn't sloped away from the engine it could get back toward the engine at low rpms. Or, if your cam isn't marine friendly, water can get sucked back.

If you have extra height in your engine compartment you may want to raise the riser further with a taller spacer, to get more slope. This is common in hot boat exhaust systems. But a stock engine should not need it.

To paraphrase Scott, but with additional details. If you have a true marine cam and a factory spec compression engine you won't get reversion at 8 degrees. I suspect rebuilders use whatever they can to build up your engine. If the cam was new what are the specs?

If you don't trust the cam, they can be measured. If it's wrong they are pretty easy to change out of the boat. Some can be done in the boat. Depends on your setup.

 

[stang32]

ok, heres another question, anyone know what the pitch should be on the engine when sitting on the stringers? i am wondering if the wngine is too high in the rear the way it is sitting now and could it be possible that is my issue. not enough slope?

 

[stang32]

First off double check that your ignition wiring contact are super clean and shiny. Battery must be fully charged.

I have personally seen sketchy ignition contacts cause poor running. Which in turn caused me to advance my timing. I had a vibrating vacuum reading while I was running then too. After I repaired that stuff I tested my vacuum (good) with a different gauge so I'm not sure if it was the gauge or the electrical problems, but I have my suspicions.



Were you seeing water entering while the engine was running? Or just while running water alone? If you were running water without the engine running were the exhaust hoses on there, or were the risers open at their ends? Were they sloped away from the engine?.
i was not able to send the scope down the riser while running due to heat so my photos were when the engine was shut down.

If water isn't entering the exhaust stream in the manifolds, risers, or elbows you should be good. Run the motor at 8 degrees btdc.
the timing has been set at 8* for a few days now and all the info i put up today is with the timing correct.
Then shut it off and check for water in the exhaust manifolds and on the spark plugs.

i did this and thats the results, a water trace from the top to the bottom, a few drops of water sitting at the bottom of the manifolds and water soaked riser hump
i did not pull the plugs again

I have a 1997 350 Mag with new factory Mercruiser manifolds and tall risers on a stand in my garage. The previous owner of my boat had them put on just before I bought it. I just went out and looked at it.
The Mercruiser risers 3/8" plug goes into the exhaust. You can look down it right into the manifold.
yup, thats were i stuck the scope in

Water from the cooling system is released at the back of the riser at the top. So if your exhaust isn't sloped away from the engine it could get back toward the engine at low rpms. Or, if your cam isn't marine friendly, water can get sucked back.

If you have extra height in your engine compartment you may want to raise the riser further with a taller spacer, to get more slope. This is common in hot boat exhaust systems. But a stock engine should not need it.

To paraphrase Scott, but with additional details. If you have a true marine cam and a factory spec compression engine you won't get reversion at 8 degrees. I suspect rebuilders use whatever they can to build up your engine. If the cam was new what are the specs?

i don not trust the rebuilder at all any more so,......

If you don't trust the cam, they can be measured. If it's wrong they are pretty easy to change out of the boat. Some can be done in the boat. Depends on your setup.

in the photo below i have in yellow the area where the scope went in and the arrow shows were yo ucan see the manifold is all wet as seen in my photo link in the post above

 

[Scott Danforth]

if your getting a stream of water with the engine off and just water flowing, you have an issue somewhere in your elbow or riser

your motor sits close to 5 degrees back while in the boat. on a 20' long trailer, that is the hitch about 6" higher than the back end.

 

[stang32]

scott, i think i created some confusion, the water coming out of the manifolds when not running occured before i took them apart and resurfaced the mating areas. it now has new gaskets and the water coming in is only when running. i

unfortunetly, i did not scope it prior tothe gasket replacement.

but i think a good idea would be to so i will run the water rthrough the manifolds with the engine off today and report the results