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Rebuilt 18V with no oil up top.

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Rebuilt 18V with no oil up top.
#1
dahlbergkm Mike Dahlberg
Tustin, CA, USA   USA
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I purchased a rebuilt 18v short block years ago. I checked it out and recently finished rebuilding it. It's in the car. I filled the oil filter and pumped in oil at a tee fitting with a gauge on it at the pressure sensor port. When I got 20 to 40 pounds of pressure, I started turning the engine over and within a minute the oil pump took over and pressure rose to 60 pounds. After a couple of minutes the engine sound changed to one of smoother operation. I'm thinking I'm good. BUT I noticed oil wasn't getting to the top end. I pulled the plug out of the rocker shaft... and no oil. I then noticed a little oil leaking from the bottom of the engine plate on the block side. I'm guessing something is plugged up. I looked at the path of the oil galley and it seems like it drops right onto the camshaft almost. Any experienced engine guys have any ideas?

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Re: Rebuilt 18V with no oil up top.
#2
balloonfoot Avatar
balloonfoot Platinum Member Lloyd Faust
Novato, CA, USA   USA
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Do you have a mismatch on the rear rocker pedestal? Early rockers on 18V head? Or vice versa.


Law of Logical Argument - Anything is possible if you don't know what you are talking about.

"Anyone with an intense emotional interest in a subject loses the ability to observe it objectively: You selectively perceive events. You ignore data and facts that disagree with your main philosophy. Even your memory works to fool you, as you selectively retain what you believe in, and subtly mask any memories that might conflict."



Edited 1 time(s). Last edit at 2024-04-20 07:36 PM by balloonfoot.

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Re: Rebuilt 18V with no oil up top.
#3
ghnl Avatar
ghnl Eric Russell
Mebane, NC, USA   USA
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1961 MG MGA "Calvin"
The rear camshaft bearing must be installed correctly so the oil pathway up to the head is open.

Also, there are two versions of rear rocker shaft pedestals. You must use the pedestal that matches the oil path in the head. One path is 'in-line' - the oil feed is in line with the bolt holes. The other is 'offset' - the oil feed is offset from the pedestal bolt holes.

Although written for the MGA, much of the info in the MGA Guru's Tech Pages also apply to the MGB. See: https://www.mgaguru.com/mgtech/engine/of101.htm


Eric Russell ~ Mebane, NC
1961 MGA #61, 1981 Alfa Romeo GTV6, 1984 Alfa Romeo Spider, 1991 Honda ST1100

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Re: Rebuilt 18V with no oil up top.
#4
dahlbergkm Mike Dahlberg
Tustin, CA, USA   USA
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I am pretty sure I checked the alignment of the rocker pedestals at the time I installed the head. I have offset rockers on a 12H1326 cast head. Thanks, Mike D.

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Re: Rebuilt 18V with no oil up top.
#5
dahlbergkm Mike Dahlberg
Tustin, CA, USA   USA
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This is a possibility, I guess. The acquaintance I bought it from swore the rebuild shop knew what they were doing. I question that from what I saw. Thanks, Mike D.

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Re: Rebuilt 18V with no oil up top.
#6
Arizona Shorty Avatar
Arizona Shorty Greg McC
Prescott, AZ, USA   USA
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1968 Jeep CJ-5
1975 Yamaha MC RD350
1977 MG MGB
1985 Jeep CJ-7
You have oil pressure, so the possibilities are narrowed. Don't run it until you have identified the issue. Since you have the ability to pressurize the system without running it, remove the valve train and pump it up.


GMc


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SDCH WTCH-X Twin Oaks Tuff Nutt
2008 - 2022

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Re: Rebuilt 18V with no oil up top.
#7
dickmoritz Avatar
dickmoritz Platinum Member Dick Moritz
Philly 'burbs, PA, USA   USA
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1326 head requires an in-line rear pedestal...

Dick



In reply to # 4787394 by dahlbergkm I am pretty sure I checked the alignment of the rocker pedestals at the time I installed the head. I have offset rockers on a 12H1326 cast head. Thanks, Mike D.


Errabundi Saepe, Semper Certi
(Often wrong, but always certain)

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Re: Rebuilt 18V with no oil up top.
#8
dahlbergkm Mike Dahlberg
Tustin, CA, USA   USA
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Thanks Dick. This is way easier than pulling the motor. I'll pull the rocket pedestal tomorrow. Mike D.

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Re: Rebuilt 18V with no oil up top.
#9
riley1489 Avatar
riley1489 Gold Member Bruce H
Great White North, QC, Canada   CAN
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1953 Jaguar XK120
1959 Riley 1.5 "King George"
1973 MG MGB
In reply to # 4787423 by dahlbergkm Thanks Dick. This is way easier than pulling the motor. I'll pull the rocket pedestal tomorrow. Mike D.

you shouldn't need to 'pull' anything.

A visual will tell you

B


Life's most persistent and urgent question is, "What are you doing for others?"


Attachments:
BH_rear pedestal.JPG    41.1 KB
BH_rear pedestal.JPG

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Re: Rebuilt 18V with no oil up top.
#10
SilasW Avatar
SilasW Gold Member Silas Kinsey
Canterbury, CT, USA   USA
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1966 MG MGB GT
There is a brass plug at the rear of the head that sometimes will fall out when the head is hot tanked and can go unnoticed. I had this happen once and the engine started and built oil pressure normally but I noticed oil dripping from the back of the engine and discovered the missing plug. I replaced the plug and everything was fine.

Silas

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Re: Rebuilt 18V with no oil up top.
#11
KozyB Avatar
KozyB George Kozak
Philadelphia, PA, USA   USA
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1971 MG MGB
As mentioned by Eric Russell, I had an issue with a misaligned rear cam bearing. Happily, I found the machine shop's mistake by chasing the oil feed path through the block with a can of WD40 and straw before assembling the engine. Machine shop did not realize (the first time around) that they had to align the holes in that bearing with 2 ports.

I hope that this is not your issue.

Best regards, George

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Re: Rebuilt 18V with no oil up top.
#12
mgblestyle Avatar
mgblestyle Philip Shave
Olympia, WA, USA   USA
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1980 MG MGB MkIV
In reply to # 4787516 by SilasW There is a brass plug at the rear of the head that sometimes will fall out when the head is hot tanked and can go unnoticed. I had this happen once and the engine started and built oil pressure normally but I noticed oil dripping from the back of the engine and discovered the missing plug. I replaced the plug and everything was fine.

Silas
Yes, as Silas notes, check that this tiny plug is intact. It is a drilling that connects directly to the feed to the rockers. The oil leak makes this a likely culprit. Phil

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Re: Rebuilt 18V with no oil up top.
#13
Speedracer Avatar
Speedracer Platinum Member Hap Waldrop
Taylors, SC, USA   USA
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1967 MG MGB Racecar "The Biscuit"
In reply to # 4787394 by dahlbergkm I am pretty sure I checked the alignment of the rocker pedestals at the time I installed the head. I have offset rockers on a 12H1326 cast head. Thanks, Mike D.

I did read all responses, but a 12H1326 head (pre smog 65-67) takes a inline oiling rocker pedestal, but you should have seen some oil inside the shaft when you removes the plug,and the offset pedestal would have bnn dumpin oil on to the top of the head the sending it to the rocker shaft .

OK I went back and looked at the other responses, Bruce pictures show it all really good. If still not getting oil to the head, then you got a second problem, either something is blocking the oil galley going form the block thru the head to rocker shaft, or as mentioned the rear cam bearing is misaligned, yes there two holes there one feeding oil tot the ear cam journal and one sending to the rocker shaft.


Hap Waldrop
Acme Speed Shop
864-370-3000
Website: www.acmespeedshop.com
hapwaldrop@acmespeedshop.com



Edited 1 time(s). Last edit at 2024-04-22 05:53 AM by Speedracer.


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Re: Rebuilt 18V with no oil up top.
#14
dahlbergkm Mike Dahlberg
Tustin, CA, USA   USA
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Thanks Silas, it's not the plug. I discovered a slight leak at the filter tube fitting at the rear of the block.

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Re: Rebuilt 18V with no oil up top.
#15
dahlbergkm Mike Dahlberg
Tustin, CA, USA   USA
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Thanks George. I've trouble shooted a couple of things and solved some and maybe found another. I hope this isn't it either.

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