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986 Boxster, Blown engine (Cracked Engine Block)


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Hi basically from my previous post, my boxster was overheating not just coz of cracked cylinder head or dirty radiator, apparently there was some cracks on the engine block, basically I need a new engine.

I have searched the net, and i found some engines, 2.5L 986 engine.

just one question

if the engine is from a 986 Boxster 2.5L Manual will it fit mine? (986 Boxster 2.5L Tiptronic)

Do i need to buy additional parts or what?

Thanks...

By the way, it really really sucks that engine needs to be changed.

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Hi basically from my previous post, my boxster was overheating not just coz of cracked cylinder head or dirty radiator, apparently there was some cracks on the engine block, basically I need a new engine.

I have searched the net, and i found some engines, 2.5L 986 engine.

just one question

if the engine is from a 986 Boxster 2.5L Manual will it fit mine? (986 Boxster 2.5L Tiptronic)

Do i need to buy additional parts or what?

Thanks...

By the way, it really really sucks that engine needs to be changed.

The 2.5 manual engine is basically the same as your Tip engine. You will need to strip some stuff off your old engine to accommodate the Tip but it should not be a big deal.

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Hi, Thanks, so basically the flywheel or the bolts will not be a problem? Do you have any idea on what are the parts that need to be stripped? btw just to be clear my boxster is a tiptronic model with a blown engine, so I plan to buy a manual boxster engine.

Also is it possible to plug in a 2.7L engine? or is that a lot of hassle? Thanks!

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Hi, Thanks, so basically the flywheel or the bolts will not be a problem? Do you have any idea on what are the parts that need to be stripped? btw just to be clear my boxster is a tiptronic model with a blown engine, so I plan to buy a manual boxster engine.

Also is it possible to plug in a 2.7L engine? or is that a lot of hassle? Thanks!

You will need to use the flex plate from the old engine and new bolts (they are single use items). You will also need any other Tip associated items (wiring harness, brackets, etc.) be moved to the new engine.

The 2.7 engines were all egas and used a different DME and sensor layout, fuel system has changes as well, so there would be considerably more stuff to develop "work around's" to make it work.

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So the wiring harness can be re-used, brackets no problem, when you say bolts are these the "cylinder head bolts" ? so everything will fit perfectly, transmission (tip transmission) to engine will all fit using the brackets from the old engine right?

ok i wont update, too much problem haha thanks in advance

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So the wiring harness can be re-used, brackets no problem, when you say bolts are these the "cylinder head bolts" ? so everything will fit perfectly, transmission (tip transmission) to engine will all fit using the brackets from the old engine right?

ok i wont update, too much problem haha thanks in advance

I was referring to the bolts that hold the flex plate to the crankshaft. The easiest way to accomplish this swap is to put the two engines side by side and move all the stuff from the original engine that is not on the replacement. When the replacement is reconfigured to the original's layout, the wiring harness should plug right in. Word of advice: Do not throw out anything until the new engine is in the car and running, some of the little stuff can be the hardest to find or replace.

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Ok Thanks so much!! I will ask the mechanic to remove both engines and transfer all the parts. I just needed to be sure that the bolts and brackets will fit right in, because for example mercedes benz, manual engine and automatic engines don't exactly fit. so just needed to be sure that the manual engine will work without changing anything. just transferring is normal, I was just worried that I need to completely change transmission or whatever.

If transfer old brackets and all is the only thing that needs to be done then that would be a lot easier. Any idea how long the whole thing will take?

Also next problem is where can we find second hand engines :D i found some on ebay btw.

Thanks

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Also next problem is where can we find second hand engines :D i found some on ebay btw.

Be very careful about where you get an engine, the 2.5L engine's were prone to cylinder wall problems, as you have already discovered. You really don't want to ship one of these long distances, only to find out you bought a boat anchor when it arrives.......

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I would've thought this would be a perfect time to look at upgrading to a 3.2L engine. The earlier 996 years weren't egas. You will need a new DME, and some engine mounts from different model altogether (I can't remember which), and again transfer bits to the new engine.

But obviously this would be a bigger undertaking.

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  • 2 weeks later...

The 2.7 engines were all egas and used a different DME and sensor layout, fuel system has changes as well, so there would be considerably more stuff to develop "work around's" to make it work.

The 2.7L engines have a slightly off-set lay-out for the intake ports, so old-style intake manifolds will not fit either.

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  • 2 weeks later...

Do note -- the engine harness for a 97 is ever so slightly different than a 99.

So if you source a 97 -- I'd swap out the harnesses.

If I remember correctly it had to do with the fuel return valve -- I think the 97 was a 2 wire

and later ones are a 3 wire -- but it's been about 3 or 4 years since I had to do that.

I think I had to alter 3 or 4 wires -- the harness mates between the chassis and the DME.

Options are limited when dealing with a non-egas (99 and earlier) unless you want to do the conversion work.

Nothing will be "plug and play".

Does anyone know if you can just take the 2.5L intake and wire harness and put it on a 2.7 long block?

Mike

Edited by txhokie4life
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Mike,

Short answer is no.

Last year I had a chance to build my Frankenstein engine: Basically a 2.7 with 2.5 internals (only difference on internals is crank, different IMS main chain and pistons). The intake ports are slightly offset between 2.5 and 2.7 engine, so they will not bolt-on as is.

Also, the fuel rails are different, so a 2.5 fuel rail will not fit a 2.7 intake manifold. And then there is the issue with the non e-gas throttle body on a 2.7 intake manifold because of the 2 vs. 1 cross pipe. This puts the whole thing at an offset so the engine cover will not fit.

Long story short, I gave up and decided to rebuild the original 2.5 engine at 143K miles, which is now running great. Replaced all worn parts, mostly bearing shells and chain ramps, using fresh bolts for crank carrier and heads.

Have a 2.7 with 2.5 internals that would run great in a 2000+ Boxster. Been on the prowl for a 2.7 donor car with failed engine. Needs to be cheap!

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  • 1 month later...
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Hi. I got a 97 Boxster Engine, the mechanic was telling me that it won't work because of the oil pump? Something about not fitting, what's the work around for this one? Thanks

Please do not double post.

Each of the first three years of the Boxster (97, 98, 99) each had a different oil pump. That said, as the pump is internal to the engine, I do not see what difference the pump makes.

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There is a difference between the TIP and manual as far as the coolant hose/connection near the thermostat.

A 97 you will need to make some modifications to the wiring harness because the purge valve and a couple

other small things are wired differently between the years.

car will run fine either way -- you just get an annoying CEL.

mike

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