Engine Swap
GREASELIGHTING
01-28-2008, 06:50 PM
Hey y'all,
Please hepl!!!:crying: I've got an 1991 Olds 98 regency with a crack block....I've found a 3800 series I, crate engine with engine/part number F(G or 9)M12338654, which the seller thinks is for an 85-87 GM vehicle. How can I tell if this is the correct engine for my car? And, if so, how differcult will the engine swap be?? All help will be greatly appreciated..........thanks
Please hepl!!!:crying: I've got an 1991 Olds 98 regency with a crack block....I've found a 3800 series I, crate engine with engine/part number F(G or 9)M12338654, which the seller thinks is for an 85-87 GM vehicle. How can I tell if this is the correct engine for my car? And, if so, how differcult will the engine swap be?? All help will be greatly appreciated..........thanks
HotZ28
01-28-2008, 09:17 PM
If the engine is from an 85-87 it is more than likely an LN3, not a L27 Series I engine, like you have in your 1991 Olds 98! They are close cousins, however, not identical. The engine part number you listed is not a current GM part number!
The LN3 was replaced by the L27 in 1991 & 92 and from 91-95 the L27 engine was referred to as the “Series I 3800”. You definitely want a 3800 block with a one piece rear main seal and roller camshaft with a balance shaft. The LN3 went through a lot of changes during the mid to late 80's, so be careful with your selection.
The amount of labor required for the engine swap, depends on your experience, age, facilities and tools required to handle the job. For the novice mechanic, this could be a very difficult and time consuming task; however, an experienced mechanic with the right tools & equipment could do the complete change in 8-10 hrs. Only you, can be the judge of how difficult this would be for you!
The LN3 was replaced by the L27 in 1991 & 92 and from 91-95 the L27 engine was referred to as the “Series I 3800”. You definitely want a 3800 block with a one piece rear main seal and roller camshaft with a balance shaft. The LN3 went through a lot of changes during the mid to late 80's, so be careful with your selection.
The amount of labor required for the engine swap, depends on your experience, age, facilities and tools required to handle the job. For the novice mechanic, this could be a very difficult and time consuming task; however, an experienced mechanic with the right tools & equipment could do the complete change in 8-10 hrs. Only you, can be the judge of how difficult this would be for you!
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