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Oil Consumption New Engine

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richie

Regular Contributor
I have 2 new 8.1 MPI 385hp cru

I have 2 new 8.1 MPI 385hp crusader engines in a new motor yacht. They only have 30 hrs. on each engine. The port engine has used one quart of oil but the starboard engine has used 3 quarts. I think I may have a serious problem with the starboard engine. What do you think ??

Richie
 
I have 8.2s (older model&#

I have 8.2s (older model) on my boat and was alarmed at the oil consumption when I first used it. I called the "Crusader's Captains Club" and spoke with a tech. who said that increased oil consumption with this engine is normal due to the "looser" tolerances with the pistons and rings in this engine. You may find that the oil consumption will settle down once the engine breaks in more.
 
"Rich,

The oil consumption

"Rich,

The oil consumption of your 8.1 should not be near the acceptable oil usage of the 8.2. The 8.2 has siamese cylinders which cause uneven cooling of the cylinders. This, along with the type of piston they use, causes eccentric expansion and contraction and uneven pistron to wall clearances. GM needed to allow extra clearance in the cylinders to accomidate this condition. The extra clearance is the reason for the oil usage in the 8.2. The 8.1 does not suffer from this engineering defiencency and therefore does not need the extra clearance. In fact, the 8.1 has o.oo" pston to wall clearance. The piston expands at the exact same rate as the cylinder.

Keep an eye on your oil levels and break in the engine as per your owners manual. The engines will use more oil during break in, but should stabilize after about 100 hours. Put in a call to Crusader, expressing your concern, but don't panic until after break in.

Good luck
Rick"
 
"Rick,

Thanks for the info.

"Rick,

Thanks for the info. I have notified Crusader and the engine is under a watch and see.

richie"
 
"Rick,
The explanation that C

"Rick,
The explanation that Crusader gave me was not as detailed but essentially was the same, that the pistons and cylinders expand/contract at different rates so increased clearances were built into the engine. But at first I had the same thing happen that Rich has, one engine used a lot more oil than the other. But after about 70-80 hours things settled down and both engines use up about the same amount of oil. I have a question I hope someone can answer. As far as I know Crusader has a very good reputation for marine gas engines, why would they (G.M.) build/use an engine with such an "engineering deficiency"? My 8.2s were built in 1999, has technology changed that much in the world of big block v8s?
thanks,
Scott"
 
"I also have 8.1 engines (

"I also have 8.1 engines (four years old now) and noticed high oil consumption first two years. Has slowed down the last two years to about 1/2 quart per 40 hrs of use. I think it is normal to see high usage of oil on the new engines. Wait until at least 300 hrs or so, and I think you will see a big change."
 
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