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BJ40 lacking power after brake, steering, suspension upgrade.


New Member
Apr 29, 2021
Country Flag
On my '77 BJ40, I recently had the brakes replaced with all disc, power steering added, and suspension upgraded with OME. Prior to this, my car would top out around 110 km/h. I now have some serious power issues and not being a mechanic I am not sure what to make of the mechanics comments. On a flat road of which there are few in Costa Rica, it tops out at 78 km/h. Going up moderate hills I can't get over about 30 km/h. Sometime worse.

Several members over at ih8mud have suggested it could be a brake issue. Either sticky clipper or other issue causing binding. One guy whether or not the mechanic replaced the residual valve. He says the drum system uses a 10lb valve whereas the disc use 2lb.

This is the reply I received from my mechanic: "...there is nothing about the new brake system that is connected to the motor because we are using a new alternator with vacuum generator and not using vacuum from the motor. The only additional load for the motor is we put the hydraulic pump and its normal to feel a little less power but just a bit".

I also got a comment asking why the springs were put on backwards after posting this photo. I have not shared this question with my mechanic yet as I am more concerned with the engine. It does seem odd to me that the wheels are no longer can tired with the wheel wells.

Any help for this non-mechanic BJ40 owner would be greatly appreciated!


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