SoCal Jet Boats
Tech Talk => Engine Mechanical / Electrical => Topic started by: mahony.2469 on July 05, 2020, 12:50:16 PM
-
When out and got wet on the 4th with the family. Boat ran good when cruising at around 2500 rpm . When into it at 3000 thru 4000 rpm puking oil badly thru breather and pcv valve....any help of why or the cause of this is appreciated......
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
Is it a new boat to you? If not, Has it never happened before? Have you made any changes?
Olds are known to do this if run a to high of an rpm for too long. Oil drain back is their downfall. They pump oil into the heads and it is slow to drain back if run too hard.
Sent from my iPhone using SoCal Jet Boats
-
Is it a new boat to you? If not, Has it never happened before? Have you made any changes?
Olds are known to do this if run a to high of an rpm for too long. Oil drain back is their downfall. They pump oil into the heads and it is slow to drain back if run too hard.
Sent from my iPhone using SoCal Jet Boats
X2 with what TD asked.
My buddies would always puke out the breather when going to high Rpms for too long. Be careful! Don't burn her up!
Sent from my LG-TP450 using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
Is it a new boat to you? If not, Has it never happened before? Have you made any changes?
Olds are known to do this if run a to high of an rpm for too long. Oil drain back is their downfall. They pump oil into the heads and it is slow to drain back if run too hard.
Sent from my iPhone using SoCal Jet Boats
Picked the boat up a few months back.it sat for five years prior. I put new distributor cap .wires plugs,carb Holley 750, air intake , baffled valve covers,gaskets, exhaust manifold gaskets, alternator,etc.it came with a pcv valve set up but I'm thinking of just running two breathers instead????
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
Fix boat up a few months ago. Replaced valve covers valve cover gaskets carburetor with a Holley 750 air intake scoop distributor cap wires plugs exhaust manifold gaskets etc. Boat came running the PVC valve set up already so just stuck with it but I'm thinking of turning it into two breathers???
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
Fix boat up a few months ago. Replaced valve covers valve cover gaskets carburetor with a Holley 750 air intake scoop distributor cap wires plugs exhaust manifold gaskets etc. Boat came running the PVC valve set up already so just stuck with it but I'm thinking of turning it into two breathers???
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
OK. So like I said, it’s THE problem with Olds boat motors. Even with 2 breathers, it will still probably happen ( I have a breather in both valve covers and it still does it). One thing that has helped is that I run 8 quarts of oil even though I have a 10 qt pan. But if I stay in it too long it’ll start to blow.
Excessive crankcase pressure could also be an issue. Boat motors should have a little more clearance between the piston and cylinder. Excessive blow by might be an issue and with the constant high rpm, trying to push that pressure out along with the build up of oil= a big mess.
It’s been argued here wether a PCV helps a boat motor or not. I personally don’t think so.
A puke tank can be added. Or if you had over the transom headers, a crankcase evacuation system.
There was a guy that went by Bunger that added external drain back lines to his Olds that helped the puking problem. I’ll see if I can find the thread.
The added breather can help a little. But it will also be another place to puke oil from if you push it too hard.
What most have said over the years, cruise an Olds with only short bursts of hi RPM.
They can be a great motor but need some machine work and modifications to without these issues.
Also check out 69Kona (his name is Lee, I think). He has a hard running Olds and was build a circle race boat with an Olds as well.
Sent from my iPhone using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
OK. So like I said, it’s THE problem with Olds boat motors. Even with 2 breathers, it will still probably happen ( I have a breather in both valve covers and it still does it). One thing that has helped is that I run 8 quarts of oil even though I have a 10 qt pan. But if I stay in it too long it’ll start to blow.
Excessive crankcase pressure could also be an issue. Boat motors should have a little more clearance between the piston and cylinder. Excessive blow by might be an issue and with the constant high rpm, trying to push that pressure out along with the build up of oil= a big mess.
It’s been argued here wether a PCV helps a boat motor or not. I personally don’t think so.
A puke tank can be added. Or if you had over the transom headers, a crankcase evacuation system.
There was a guy that went by Bunger that added external drain back lines to his Olds that helped the puking problem. I’ll see if I can find the thread.
The added breather can help a little. But it will also be another place to puke oil from if you push it too hard.
What most have said over the years, cruise an Olds with only short bursts of hi RPM.
They can be a great motor but need some machine work and modifications to without these issues.
Also check out 69Kona (his name is Lee, I think). He has a hard running Olds and was build a circle race boat with an Olds as well.
Sent from my iPhone using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
Thanks for the info..... I'm gonna try and run two breathers and see what happens....a little oil I can handle but if it's still bad I'm gonna invest in a puke tank
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
http://www.socaljetboats.com/engine-mechanical-electrical/crankcase-pressure-in-an-olds-question/?PHPSESSID=t68tl0ge104j0af4v2ea9ppsr1
This thread has a link to “The Olds Article” and shows the external drain back and some other info.
Sent from my iPhone using SoCal Jet Boats
-
Thanks for the info..... I'm gonna try and run two breathers and see what happens....a little oil I can handle but if it's still bad I'm gonna invest in a puke tank
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
In my experience, it will still puke oil with two breathers. Do you have tall or short valve covers? Baffled tall will help. Run it at least a quart of oil less than capacity. The crank windage really does whip the oil and makes it worse. I ditched the PCV and ran a dual line catch can with tall baffled valve covers. That definitely helped. You should also consider installing pipe cleaners inside of the pushrods to slow the oil pumping up to the top. Be mindful of your high rpm bursts.
-
In my experience, it will still puke oil with two breathers. Do you have tall or short valve covers? Baffled tall will help. Run it at least a quart of oil less than capacity. The crank windage really does whip the oil and makes it worse. I ditched the PCV and ran a dual line catch can with tall baffled valve covers. That definitely helped. You should also consider installing pipe cleaners inside of the pushrods to slow the oil pumping up to the top. Be mindful of your high rpm bursts.
I had Hardin Marine valve covers in baffled first then I went to come plated baffled ones. 4 in. Tall
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
I have a thought of running drain back lines off of the breather holes to the oil fill tube by tapping hose nipples into the sides of it then running a big breather for ventilation off the top of it??????? Just a thought any feedback is appreciated......
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
i have had a lot of experience with the olds oil puking . mine use to even come out of the distributor gasket. what the issue is the olds pumps all its oil into the heads and does not drain back fast enough!! if you do some looking around on olds sites you will find where the racers have actually drilled drain lines from the back of the heads to the pan with good results.. may not be something you want to do but its probably the best way!
-
i have had a lot of experience with the olds oil puking . mine use to even come out of the distributor gasket. what the issue is the olds pumps all its oil into the heads and does not drain back fast enough!! if you do some looking around on olds sites you will find where the racers have actually drilled drain lines from the back of the heads to the pan with good results.. may not be something you want to do but its probably the best way!
Thanks .... I've read that thread it's just a little above my mechanic skills. I drill in the wrong location, I'm buying new heads...
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
i personally dont think the rpm is your problem, we ran our 69 tahiti with 455 BBO for 15 years, 3 different versions of the same motor. it would only ever just drip out of the breathers occasionally. Maybe 10 drops after 45 minute runs averaging 3500 - 4000 rpm constant. (Avi to pirate cove or pirate cove to the sand bar.)
i personally feel you have excessive blowby or excessive oil in the heads from some other issue.
you can also pull the valve covers off and make sure there is nothing blocking the oil returns in the heads. 2 per head, front and back.
-
i personally dont think the rpm is your problem, we ran our 69 tahiti with 455 BBO for 15 years, 3 different versions of the same motor. it would only ever just drip out of the breathers occasionally. Maybe 10 drops after 45 minute runs averaging 3500 - 4000 rpm constant. (Avi to pirate cove or pirate cove to the sand bar.)
i personally feel you have excessive blowby or excessive oil in the heads from some other issue.
you can also pull the valve covers off and make sure there is nothing blocking the oil returns in the heads. 2 per head, front and back.
Thanks for the info.... I just read a blog on the internet last night about those getting clogged. I'm gonna pull the valve covers and check it out, or clean them out. I have G heads and believe the oil return holes are on the left and right hand corners?
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
Thanks for the info.... I just read a blog on the internet last night about those getting clogged. I'm gonna pull the valve covers and check it out, or clean them out. I have G heads and believe the oil return holes are on the left and right hand corners?
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
all factory iron heads are the same. if it was sitting for a long time, possible something got in.
-
all factory iron heads are the same. if it was sitting for a long time, possible something got in.
I just pulled the valve covers and from what I can see the drain back holes appear to be clean.
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
frankly if it were mine , id just deal with it puking. go get some of those oil absorbing mats and keep them with the boat. and wipe down the motor after each use . its just very common . on an olds!
-
Have you done a compression check or a leak down test yet? If it is blow by you will be chasing the dragon.
Sent from my iPhone using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
I just pulled the valve covers and from what I can see the drain back holes appear to be clean.
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
did you put a clothes hanger wire through them to make sure, head and block together should only be about 3" max to get through.
Also, next time it happens, pop the oil fill tube cap off and see if a bunch of air is pushing out?
Is this the first time you have had the motor running on the water?
-
did you put a clothes hanger wire through them to make sure, head and block together should only be about 3" max to get through.
Also, next time it happens, pop the oil fill tube cap off and see if a bunch of air is pushing out?
Is this the first time you have had the motor running on the water?
Have ran the boat a few times and been working out the issues. I did away with my pcv valve and am running two breathers on valve covers and I put a breather on my oil filler for added ventilation along with new valve cover gaskets..... Going to run it next weekend.....thanks again for all your input..
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
Looks good
Sent from my LM-V405 using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
-
Have ran the boat a few times and been working out the issues. I did away with my pcv valve and am running two breathers on valve covers and I put a breather on my oil filler for added ventilation along with new valve cover gaskets..... Going to run it next weekend.....thanks again for all your input..
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)
Nice! is that a holley intake?
-
Nice! is that a holley intake?
Brand new Holley 750 carb and new air scoop...old school offenhauser intake
Sent from my 5032W using SoCal Jet Boats mobile app (http://r.tapatalk.com/byo?rid=201)