Perkins 4-154 rear oil seal

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Al

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Okay Forum members, now a serious inquiry. Our engine is a Perkins 4-154 of around 1986 vintage. As per the history of these engines, the rear oil seal is leaking and increasingly so, as well, the Velvet drive reduction gear is losing oil into the bell housing and into the drip pan beneath the engine.

I have purchased the more exotic Teflon rear seal (two pieces) and the output shaft seal for the reduction gear. I have my wrench man on schedule to do the actual operation.

Okay then, What is there to expect? The shaft will be disconnected and slid back in place, the reduction gear will be lifted out, a scissor hydraulic jack will be employed to (1) hold the engine in place with the gear out and (2) raise the engine to gain more access to the rear of the engine.

Question: The bell housing comes off? The flywheel comes off? The seal is separate from the Crankshaft, meaning that the oil pan will not be required to be removed?
I am aware from reading elsewhere, that the seals themselves have to be allowed to extend above the cap by 1 inch after the seals have been put in place.

Any history or knowledge on the issue is truly welcome.
Al
:blush:
 
Al, boatdiesel.com may be a better source for these answers. I will say- that if you have a two piece seal it will likely require removing the rear crankshaft main bearing cap- this means the oil pan would need to be removed. A one piece seal usually knocks into a bolt on housing around the rear of the crankshaft. Keep us posted.
 
Forklift, Wow, as soon as I saw the handle I became excited!! Many forklifts utilize Perkins four cyl. engines. Then- - - -

Had read some to the post there on boatdiesel. They are quite providential unlike this Forum where you can access both sides of the discussion. You are correct, most likely after joining one may fine a response. Was or am hoping that something here would pop up so as to avoid yet another forum membership. Bottom line being that the job is going to happen regardless. The employed shop shows no fear which on one hand is encouraging, on the other what cost "Fear" Hummmmmmmm.
Thanks for the suggestion. You have led the horse to water now- - - - - -
Al:dance:
 
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QUOTE:"Had read some to the post there on boatdiesel. They are quite providential unlike this Forum where you can access both sides of the discussion. You are correct, most likely after joining one may fine a response. Was or am hoping that something here would pop up so as to avoid yet another forum membership. Bottom line being that the job is going to happen regardless. The employed shop shows no fear which on one hand is encouraging, on the other what cost "Fear" Hummmmmmmm.
Thanks for the suggestion. You have led the horse to water now- - - - - -
Al:dance:"


aa Wanted to report to the forum on the success of installing the rear seal on out 4-154 Perkins. As the quote above said we were apprehensive to the job. Our fears were unfounded. The mechanic flew right at the project.
He employed the neatest chain come along, little bitty thing to hold the engine up off the rear reduction gear mounts. Shaft slipped aft, reduction gear hoisted out, bell housing off, starter off, fly wheel off, tension/spring plate off, There are three oil pan bolts that have to be removed. THE REAR SEAL IS IN A BLOCK THAT IS REMOVED. There is no need to touch the crankshaft.
The mechanic was a bit appalled at the skimpy seal and housing. He is use to Cummings, Cat and such.
The rebuild was as fast going back. Total of 12 billed hours @120.00, bits and pieces total of $1500.00.
Cheap at 1/2 the price.
Fortunate to acquire the service. Mechanic stated that the shop caters to commercial/fishing fleet and rare to take on a private pleasure boat.
Cheers-
Al -Ketchikan(Bridge to Nowhere) Alaska:dance:
 

QUOTE:"Had read some to the post there on boatdiesel. They are quite providential unlike this Forum where you can access both sides of the discussion. You are correct, most likely after joining one may fine a response. Was or am hoping that something here would pop up so as to avoid yet another forum membership. Bottom line being that the job is going to happen regardless. The employed shop shows no fear which on one hand is encouraging, on the other what cost "Fear" Hummmmmmmm.
Thanks for the suggestion. You have led the horse to water now- - - - - -
Al:dance:"


aa Wanted to report to the forum on the success of installing the rear seal on out 4-154 Perkins. As the quote above said we were apprehensive to the job. Our fears were unfounded. The mechanic flew right at the project.
He employed the neatest chain come along, little bitty thing to hold the engine up off the rear reduction gear mounts. Shaft slipped aft, reduction gear hoisted out, bell housing off, starter off, fly wheel off, tension/spring plate off, There are three oil pan bolts that have to be removed. THE REAR SEAL IS IN A BLOCK THAT IS REMOVED. There is no need to touch the crankshaft.
The mechanic was a bit appalled at the skimpy seal and housing. He is use to Cummings, Cat and such.
The rebuild was as fast going back. Total of 12 billed hours @120.00, bits and pieces total of $1500.00.
Cheap at 1/2 the price.
Fortunate to acquire the service. Mechanic stated that the shop caters to commercial/fishing fleet and rare to take on a private pleasure boat.
Cheers-
Al -Ketchikan(Bridge to Nowhere) Alaska:dance:
I joined the forum to find out how the teflon rear main seal is doing. I have the same engine out of our sail boat replacing the main seals. I would like to know where you purchased the seal, as I can't find anything except the original rope seal. I have 7500 hours on the engine and it runs great. Has good compression and has been very reliable. Only problem is the seals. Hope to get another 3000 or 4000 hours out of it. My wife I I just returned from 10 years live aboard, about 6 of those years in Europe and the Med. We have a 1985 Amel Maramu ketch.

Ken and Judy
 
Ken- Welcome to the forum! You will absorb tons of information,instruction, debate,humor, and best of all the comradidie of a huge bunch of willing boaters in sharing, offering a helping hand. I have never regretted joining looking forward each day to read the latest or respond. It is hoped you will do so as well. Now to your inquiry. Here is the seal that I obtained:

4 108 4 107 4 154 Perkins Rear Seal Kit | eBay

The article description starts referencing the 4-107 and 108 then includes the 154. We purchased and it came quickly. That is the good news, our engine shop was shocked when they had the rear seal housing in their possession. Their first words were "There is no warranty on this project". I had to agree without a second thought. This housing and application has to be the most outlandish engineering designs that somehow passed the quality control at Perkins.
Within 10 hours the silicone seal began weeping. Yes, the seal removed was leaking a quart in 12 hours of normal 2150 RPM operation so there has been a improvement.
As parts for the 4-154 are becoming hard to obtain or a wait to receive plus our engine being of somewhere South of 1974 built we have determined and decided to have this engine replaced with a running takeout Perkins 4-236 of a more current date (2003)with low engine hours.
So there is a Perkins 4-154 with a 3:1 BW gear and a backup Westabeke W58 (Perkins/Mazda-154) with a gear-ratio unknown, available

One of the sites carried a conversation, and my son confirmed, that excess crankcase pressure will often result in reverse pressure on seals. In this case the crankcase pressure will seek weak points of which the rear seal is. Our engine does show crankcase back pressure so well may be a main reason of the leaking continuing. Thought about adding a second breather hose from either a soldiered nipple in the valve cover or a Ford breather adapter that fits the oil cap on the valve cover, in the end the engine change won out just for the engine age and the lack of ready parts inventory.
There you have the ugly of it.
Regards,
Al-Ketchikan (Bridge to Nowhere) Alaska
 
Well, thanks for that information. I had seen the Foley replacement for the 4108 and didn't know it was the same piece for the 4154. I agree, the seal design is pretty pathetic. I guess I'll just go with the original from TAD. I hope the seal design is better on the 4236 for you.
 
Ken, You are welcome. Point in mind regarding the engine models, in their heyday oil leaking was not frowned upon as it is today. In most applications I'd suspect the leakage was either acceptable or the seal was more accessible for replacement. That being said to the huge number of commercial applications the 4-154 particularly was employed. In my research finding a number of credible engine manufactures who purchased or manufactured under licence this model.

Happy to report the rear seal on the 4-236 is more substantial.

Hope you are one of those 4-154 who makes the rare "Never leaks again"
achievement.

Al
 

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