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jdifran98

  • Karma: +0/-0
Olds 455 oil
« on: July 20, 2021, 08:45:14 AM »
Hey everyone, just bought my first jet boat! It’s a 1972 rayson craft with a 455 olds, mild cam, mondello oiling mods, and a Berkeley pump with the Jetovator.
Boat runs like a top, only problem is that the breathers puke pretty bad at anything over 3500 rpm. Guy I bought it from told me he put 11 quarts 20w50 in it. He bought the boat 2 years ago and the owner before him told him to do that. It looks like the boat has a moroso flat bottom 10qt pan but I don’t know for sure. The dipstick is useless as the older owner said it was homemade and reads high. The oil gauge only reads 25ish psi once the boat is warmed up and running for a while. Right now I’m thinking there’s too much oil and the crank might be whipping up the oil and introducing air into it, causing the low pressure along with the breather issue. I’m not really worried the engine isn’t being oiled properly as it has a fair amount of hours on it as is, so if it wasn’t being oiled properly it probably would have spun a bearing by now. Any way for me to check the accuracy of my oil gauge too? Any input/opinions on this would be appreciated!
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TrollerDave

  • Karma: +32/-0
Re: Olds 455 oil
« Reply #1 on: July 20, 2021, 09:38:45 AM »
Welcome to SCJB and jet boats. Good looking boat.

Not sure if you’re aware, Olds are known for oiling issues. They have a poor drain back system and tend to pump all the oil up into the valve covers which usually leads to the puking. Assuming you don’t have a blow by issue, it is pretty common.


https://www.marineindustrieswest.com/GroupCatProducts.cfm?group_id=6&catid=898

They make 10 qt and 14qt pans. If you had a 14qt, I could see running 11qts of oil. But I’ve never heard of adding an extra qt. Usually you would go less. I have a 455 with a 10 qt pan and run 8 qts. Olds motors can’t be run at high rpm for very long unless drain back mods have been made.

Do you have an electric oil pressure gauge? Some guys have the electric in the dash but tee a mechanical gauge back by the engine somewhere.
I have breathers and OTT headers. I have to keep an eye on the breathers to make sure oil isn’t spraying out. When I first got my boat,  I was cruising to fast and my buddy tapped me on the shoulder and pointed at the engine. Oil puked on the headers and caught fire. No damage but, That clean up sucked!


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jdifran98

  • Karma: +0/-0
Re: Olds 455 oil
« Reply #2 on: July 20, 2021, 09:45:54 AM »
Welcome to SCJB and jet boats. Good looking boat.

Not sure if you’re aware, Olds are known for oiling issues. They have a poor drain back system and tend to pump all the oil up into the valve covers which usually leads to the puking. Assuming you don’t have a blow by issue, it is pretty common.


https://www.marineindustrieswest.com/GroupCatProducts.cfm?group_id=6&catid=898

They make 10 qt and 14qt pans. If you had a 14qt, I could see running 11qts of oil. But I’ve never heard of adding an extra qt. Usually you would go less. I have a 455 with a 10 qt pan and run 8 qts. Olds motors can’t be run at high rpm for very long unless drain back mods have been made.

Do you have an electric oil pressure gauge? Some guys have the electric in the dash but tee a mechanical gauge back by the engine somewhere.
I have breathers and OTT headers. I have to keep an eye on the breathers to make sure oil isn’t spraying out. When I first got my boat,  I was cruising to fast and my buddy tapped me on the shoulder and pointed at the engine. Oil puked on the headers and caught fire. No damage but, That clean up sucked!


Sent from my iPhone using SoCal Jet Boats

Thanks! And yup I’m aware of the olds characteristics, my engine supposedly has a lot of mondello drain back oiling mods done to it to help it. I’m not sure of the pan size, I’m guessing 10qt because that’s what I was able to find online that looks similar, and I wasn’t able to find an 11qt pan. It is an electronic gauge, gonna look for a mechanical one I can T into the system to double check it, thanks for that idea. My plan for now is to take a quart out of the boat and see how it reacts, and maybe take another quart out if the problem persists. Also putting new breathers on the boat this weekend as the old ones were rtv’d on and were pissing oil out right at the valve cover.
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76Mantra455

  • Karma: +7/-0
Re: Olds 455 oil
« Reply #3 on: July 20, 2021, 07:15:18 PM »
My bud had the same issue with his olds then it eventually threw the bearings in it… I have a olds and it good and no issues with the engine and I run it hard sometimes and may have a drop that comes out the breathers. I run the 20 50 vr1 valveoline and have a stock oil pan holds 6 quarts with filter change. When I purchased the boat about 4 years ago the guy I bought it off of said all these things were done best thing to do is tear it open and make sure so you don’t end up blowing it. Do a leak down test pull the pan check the oil pump pick up. I run a regular oil pump no high volume. Also check your valve covers make sure they have baffles in them that will cause oil coming out the breathers if you have no baffles in them. What temp you running? My oil pressure starts out around 60 psi and after running for a few hours constantly and in the throttle it will drop to round 40 psi. I had 3 oil gauges up until July 4th weekend pneumatic electric and manual the tube broke off and I had to easy out the brass tube out the block and just use the manual one. At the beginning when I had it had all kinds of oil in issues but not no more. Also after the leak down test do a compression test as well. What kind of heads are you running? I originally had a set of J heads and I would blow oil out the breathers till it was saturated I found a set of big valve C heads and have like I said maybe a drop to wipe off the valve covers… good luck and hope it is just too much oil let us know how it turns out. Also welcome to the site and good looking float


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jdifran98

  • Karma: +0/-0
Re: Olds 455 oil
« Reply #4 on: July 21, 2021, 05:21:14 AM »
My bud had the same issue with his olds then it eventually threw the bearings in it… I have a olds and it good and no issues with the engine and I run it hard sometimes and may have a drop that comes out the breathers. I run the 20 50 vr1 valveoline and have a stock oil pan holds 6 quarts with filter change. When I purchased the boat about 4 years ago the guy I bought it off of said all these things were done best thing to do is tear it open and make sure so you don’t end up blowing it. Do a leak down test pull the pan check the oil pump pick up. I run a regular oil pump no high volume. Also check your valve covers make sure they have baffles in them that will cause oil coming out the breathers if you have no baffles in them. What temp you running? My oil pressure starts out around 60 psi and after running for a few hours constantly and in the throttle it will drop to round 40 psi. I had 3 oil gauges up until July 4th weekend pneumatic electric and manual the tube broke off and I had to easy out the brass tube out the block and just use the manual one. At the beginning when I had it had all kinds of oil in issues but not no more. Also after the leak down test do a compression test as well. What kind of heads are you running? I originally had a set of J heads and I would blow oil out the breathers till it was saturated I found a set of big valve C heads and have like I said maybe a drop to wipe off the valve covers… good luck and hope it is just too much oil let us know how it turns out. Also welcome to the site and good looking float


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Not sure on oil temp, but the engine runs around 140-150, have the water intake adjusted so that the headers are very warm to the touch but not scalding hot, boat seems happy. Oil pressure pretty much stays around 25 psi. Running ga heads on it.

Will update after this weekend, planning on taking 1-2 quarts out of it in small increments and seeing how it reacts. And thanks! I’m already in love with it lol


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FordLover

  • Karma: +72/-0
Re: Olds 455 oil
« Reply #5 on: July 21, 2021, 11:16:58 AM »
Yes, take out some oil. You are probably sloshing it around in the pan being so full. Could even help your oil pressure.

Man, brings back memories. Thinking back to 1999. I had a 19 foot California with a 200hp weed whacker on it. My buddy who thought that was super cool having a boat too, bought a miller with an Olds 455 in it. EVERYTIME, he hit the throttle hard for more than a few seconds oil would spew out his breathers all over the transom. Good times! Lol. Weirdly good memories.

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jdifran98

  • Karma: +0/-0
Re: Olds 455 oil
« Reply #6 on: July 21, 2021, 11:53:22 AM »
Yes, take out some oil. You are probably sloshing it around in the pan being so full. Could even help your oil pressure.

Man, brings back memories. Thinking back to 1999. I had a 19 foot California with a 200hp weed whacker on it. My buddy who thought that was super cool having a boat too, bought a miller with an Olds 455 in it. EVERYTIME, he hit the throttle hard for more than a few seconds oil would spew out his breathers all over the transom. Good times! Lol. Weirdly good memories.

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Hahaha sounds like good time! I’m thinking that with so much oil the crank might be whipping up the oil and adding air to it, lowering the overall pressure. Hopefully taking some out helps both problems.


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jdifran98

  • Karma: +0/-0
Re: Olds 455 oil
« Reply #7 on: August 10, 2021, 11:14:41 AM »
So, just wanted to update the thread. Got new breathers and took out the old ones, valve covers are baffled. The new breathers didn't help so I ended up taking out about 1.5 - 1.75 quarts of oil. The boat puked a decent amount out over the past few weekends I've been using it too. So all in all, the boat had 11 quarts in it according to old owner, and its probably down around 9 quarts now. Puking is almost completely gone! I had the boat out this past weekend and was getting on it pretty hard for a while and it only leaked a small amount of oil from one breather after multiple wide open pulls. The oil pressure is also slightly better too. Before, if I idled around for a couple minutes and then got on it I'd see 30psi MAX, now it sits around 40 and slowly edges it's way back down to 27ish psi at a 3000 rpm cruise. Although I know this is a little low, I'm not too worried about it because as I said before, if this was a problem the engine most likely would've spun a bearing a while ago as it's been running like this for some time.
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TrollerDave

  • Karma: +32/-0
Re: Olds 455 oil
« Reply #8 on: August 13, 2021, 11:40:42 AM »
Thanks for the update. I figured 11 quarts was too much. Glad to hear it’s better. I’m always watching the oil and temp gauges. I don’t think the lower pressure is the issue vs oil temp.


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96Laveycraft21Xt

  • Karma: +0/-0
Re: Olds 455 oil
« Reply #9 on: October 14, 2021, 04:16:31 PM »
Glad its getting better!

When i had my first olds on the Dyno, i had a 7qt moroso pan (car) and the dyno operator put all 7 qts in and a quart of comp cams break in additive.  After break in  we made a first pull forgetting that we had the extra oil in it. Oops! haha  oil pressure was good but the pressure dropped all the way as rpms increased.  realizing the error right away, we drained the oil (15w40) and put in the 20w50 i planned to run.  Oil pressure increased with rpm and gained 15 hp as the crank was hitting the oil and foaming it, even with the thicker oil
  • Boat #1: '96 Laveycraft 21' XT Ski
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