Gasket replacement between the enginer and the pipes under intake manifold

I just replace the water pump on my Prius the first time by myself since it was manufactured with over 170K miles. and after replacement, I found that there is something leaking. It is a pipes underneath the intake manifold and mount directly to the engine. I want to fix it by buying a gasket and fix it myself. Anyone know what is those pipes? I cannot find it anywhere on internet. The leak was small but I do want to fix it.

by the way, I don't even know what it is leaking. doesn't look like oil. It is most likely coolant if I am correct. but I thought the coolant suppose to be in pink.

 

Good advice. I actually bought the entire service manual somewhere on internet for $5.

 

Found it. That is call water by-pass pipe. and I need water by-pass pipe gasket. Not sure how I will do it. I mean not sure I will have to remove the intake manifold. If I have to remove the intake manifold. Most likely need to buy intake manifold gasket too.

 

No, I cannot find in the manual how to remove it. It did show that to remove the cylinder head, I need to remove everything. That include the water bypass pipe and intake manifold. I should be able to access both nuts by removing just the throttle body. Will see

 

Look like I cannot be lazy. I have to remove the intake manifold. Anyway, just order the manifold gasket as well. Maybe I will do all the work this saturday or sunday. It may be good idea to replace all the coolant as well.

 

Update:

Job was done this passed weekend. took me about 6-7 hours to complete everything.
thermostat and thermostat gasket were replaced also for the first time since it was manufactured with over 174K miles right now. intake manifold gasket was replaced also since the gasket was not expensive. throttle body was cleaned also with air blower from my air compressor. Replace PVC value too since I have remove a lot of thing already.

Will keep an eye on possible water leak.

I believe there are still air in the cooling system but should not be a big worry in a short run since the weather is not hot these days and prius engine does not generate a lot of heat compare to other car. But definitely need to work on it as soon as possible to remove all air.

One thing I found that when I change the inverter coolant few days before, there were small amount of coolant around the bolt. This is bad. It definitely mean that replacing the washer when changing the inverter coolant is very important. I guess I have to do that part again this coming weekend and waste the coolant that I put in few days ago. In fact, that was the first time I change the inverter coolant since I have the car with over 174K on it.

Next thing for me to do, transmission fluid change, which I have done on this car for 3 times already

 

This is very good idea! I did not think about that! my stupidity does not want to leave me alone. Anyway, I will order the washer as soon as possible. Maybe good to other the washer for the transmission bolt too since I will work on it soon. (Is there a washer for the transmission drain bolt ??, I totally forgot)

 

I have already done that. and the heat from the cabin heater was actually very hot. The only thing that I haven't done is put the car in inspection mode and let the car engine run until the radiator fan turn on. And I will do it tonight since my Lisle funnel will arrive tonight.

One thing that I was not sure was the upper radiator host was hot for few miles of driving. but the lower host was cool. Not sure this is normal for Prius. All I can tell is this indicate that the thermostat does not want to open. This is strange. But I did test the new thermostat before I install it. And it opened with boil water. I did not test it will water from cold to hot and measure that it open at 82C. I should have done that and not assume that it will just work before I install it.

 

Yes, this is how I think. not sure my thinking is correct or not. but you confirm it. I guess that is why the radiator fan also almost never turn on unless it is in a very very hot day with AC on. But it should not be cool, it should be at least warm, right? That is what I was not sure why the lower host is so cool that I did not feel that the thermostat was ever opened.

 

Putting it into inspection mode this morning and all air should be removed. no additional coolant was added. and not a lot of air coming out. Also, doesn't look like there were any leak from anywhere. the fan turn on at least 5-6 times. but each time it was on, it only stay on for about 3 seconds. very short time. both upper and lower hosts from the radiator to the engine were very very hot. So thermostat did open. after driving on highway to work for about 30 minutes with AC on, lower host was cool and only upper host were hot.

next thing for me, transaxle fuild and replace inverter drain washer. then, brake pad and drum on the rear wheel. After that brake on front wheel too. then I may replace the struts. I replaces the struts when it was at 135K (three years ago). too many holes on the road in Boston. Also the quality of the struts from Toyota may be declining . I think I should consider KYB. Especially it costs only $240 at amazon for all four struts. It is possible that KYB is better than original Toyota struts since Toyota want you to buy a new Toyota prius.