94 SC400 Misc. Repair

[yodathespian87]

So I have a few questions for you guys and didn't want to have bunches of different threads open. So I recently bought the 94 SC400 for $500 for a swap that I hope to do in the future. I bought it up in Denver and on the drive back home to Colorado Springs (about 60 miles) I noticed it overheating in less then 15 miles. Checked and no fluid. Let it cool. Tried to make it to a gas station and the timing belt broke. Towed it back and just replaced the timing belt and the idler pulley. (which had exploded)

Now that I have it running I went to fill it up with antifreeze and I found it pouring out the bottom of the engine near the front axle. Still need to figure that out so any pictures or routing or coolant lines would be most helpful.

The other problem is that when I accelerate to 2K RPMs it dies off for a sec or 2 and then it kicks back in. Wasn't entirely sure what that is. Possibly the fuel filter is clogged or fuel pump needs to be replaced. Any input on this would also be helpful. Thanks guys

 

[Lextreme II]

You should have change the water pump also when u did the timing belt. Now you have to redo the whole thing again.

 

[yodathespian87]

What would that have to do with dripping? Or pouring? What about freeze plugs? It looked good when I replaced the belt.

 

[yodathespian87]

Talking to a coworker and he said that the engine quiting out at 1800 RPM could be the mass air flow sensor. Is that a common problem with Lexus/ have any of you had that problem?

 

[Zuffen]

The water pump is used as an idler for the cam belt.

You would have seen the large (2") pulley in the front of the engine that the cam belt loops around on its way from one head to the other.

If the water pump is leaking the water comes out the bottom of the engine where the crank angle sensor is, that's the wire runing into the engine below the crank pulley.

I would replace the water pump and the tensioner you didn't replace and then see how it goes before you go off chasing "other" gremlins.

These engine are complex yet simple at the same time.

Do one thing at a time.

Get it running without overheating then worry about any other problems that show up.

 

[yodathespian87]

Okay thanks, looking yesterday and followed the leak up to... the water pump. I didn't know that it doubles as an idler as well. I will take care of that this weekend. Thank you.

 

[yodathespian87]

Does anyone have know where the antifreeze inlet goes on the radiator? Mine was not attached from the fill resevoir to the radiator. There is a spout on the bottom of the radiator but when I hooked it up it didn't fill up the radiator. Thanks

 

[yodathespian87]

So I replaced the water pump and the leak is gone, the timing is great and she runs wonderfully. So on to more repair questions. Were is this fuel filter? And the fan is that hydraulic or something? (meaning it has a reservoir) Cause mine is missing the lid and has vacuum if I cover it with my palm so I'm thinking its important.

 

[stevechumo]

The fuel filter is located under the car near the rear wheel on the driver side. It's also near the door molding at the bottom.

The fan is hydraulic if you see the hoses coming out of the fan and go to the pump in front of the engine. There's a pulley right in front of the pump as well. I removed the hydraulic fan on my SC400 2 years ago, so I don't remember exactly where it is. However, I think its resevoir is hanging on the radiator near the battery. If the lid is missing, dirt will get in the oil and will clog your pump along with the fan, and it'll kill the whole fan system.

 

[yodathespian87]

Thanks I figured that was the deal with the fan. And I will check out the fuel filter situation. Thanks

 

[spf_lexus]

hey bro do you by chance go to CSU Pueblo? If you need some help im about 25min south of you. you could be seeing w-pump bearing failure @2000rpm. freeze plugs would be my only other idea.

 

[yodathespian87]

No I don't go there or to any college. I solved the water leaking problem, it was the water pump. It drives now and works good. I need to solve the fuel filter problem. Which I hold the gas peddle at 2000 RPMs and it will starve for gas . But works if I pounce on the gas. So I'm thinking its a fuel issue. First checking the filter then the pump.

 

[yodathespian87]

Ok so that isn't looking like the fuel pump due to the fact that its only between 1700-2000 RPMs. Throttle Position sensor? And my heat/ ac fan doesn't seem to be working. Any suggestions? Thanks

 

[V8Datto]

Check your exhaust, If it's blocked the engine will build up pressure and won't rev

I've had a catalytic converter block up before,

 

[stevechumo]

Just in case if your hydraulic fan breaks or doesn't work, swapping to electric fans may save you some money.

 

[yodathespian87]

Ok thanks guys I will check the exhaust and see if that may be it. By the way, goofy question but where is my window cleaner container? I can't find it and I have nothing to spray my windshield. I'm thinking it never got replaced after the previous owner crashed it.

 

[stevechumo]

Ok thanks guys I will check the exhaust and see if that may be it. By the way, goofy question but where is my window cleaner container? I can't find it and I have nothing to spray my windshield. I'm thinking it never got replaced after the previous owner crashed it.

The windshield resevoir on the SC is next to the battery. Mine isn't working either.

 

[yodathespian87]

ha ha ha thanks. Yeah its missing then. As for the previous posts about the exhaust buildup might being my RPM problem, I don't think that is it cause I do get the higher RPMs. It's only skips between 1800-2000 Rpms.

 

[spf_lexus]

Check the plugs and their gap? I had a bad miss in your rpm range and it was just a set of dirty plugs. Also, if your wires are not new, check them for arching in a blacked out garage with the car on, hood open.

 

[yodathespian87]

Okay good idea. I will check those. Anyone know the correct gap on those?