Not sure whether to put in integra forum or not, but i have a 93 civic hatch. b20 block, b16 lsd tranny, gsr head. Titanium rods, titanium valve springs and retainers, bored to 1.9, larger valves, port and polished, you know... lots of good stuff to go vrroom vroooomm. But i just finished dropping this motor in this car and it ran ok before i started to do all this work. Now if im driving along on the highway, then go into neutral it overheats. Also, if i am cruising along at lets say 80 mph in 5th gear, then floor it for 20 seconds, it'll instantly overheat. Fan is on, fluids are topped off. It has a new water pump. Thermostat is opening. Im stumped. any ideas?

 

Are you sure you aren't leaking coolant what happens if you park it and let it idle 1.9L ? so like 83mm bore?

 

It doesn't leak whatsoever until it starts boiling. When i say overheat, i mean my gauge crawls all the way to its max. I pull over and my overflow is boiling and starts to drip out the top. I took it for a steady 70 mph trip for 40 miles and when i parked it wasn't hot or leaking. But it doesn't like neutral.

 

i'm guessing it overheats and you keep on driving it as it goes away when moving ? you may have warped the head if done enough, when the car is parked and cold check the coolant lvl. did you bleed the coolant sys properly after changing the t-stat ?

 

Yes cooling system was bleed, head is NOT warped. It was 100% stripped down, resurfaced, machined out a bit for larger valves, and new EVERYTHING inside. Took it to a machine shop and paid big bucks to get it built right. Fluids when cold is topped off. thermostat is new and there is no air in system. And if it hits the H when im on it or in neutral, i can put it in 5th and don't touch the gas pedal and just coast and it starts to go down slowly, but id rather just pull over. I'm stumped... i really am...

 

overheating usually means it's not bled completely. are you doing the procedure correctly? like running it with the heat on on an incline with the cap off? could also be your rad cap is broke. hopefully you haven't done any damage to your engine letting it overheat to H multiple times

 

Is the fan pulling in air? The fan might be in reverse? Just a thought

 

Fan is not in reverse. Its the same fan i've been running for my past few motors. Also, it is bleed correctly, i have done it many times, this is like my 12th motor i've put in this car. I don't have a heater, its an autocross car so it's stripped to it's bones, 16 point cage, no blower / heater, etc. But im sure no air is in the system. It's bugging the hell outta me

 

Where did you get the water pump from?

 

I actually got my waterpump from the local Honda dealership parts department. Everything else has been purchased from online stores, password jdm, summit racing, etc.. and from companies directly. Pump is NEW. not reman

 

are you sure its overheating? not a faulty ECT sensor?

*edit*
derp. just read u say its coming out the overflow.

do a compression test and leakdown. there are many reasons why your overflow is overflowing. blown piston rings is one of em

 

Buy a OEM radiator cap.

Pressure the coolant system when it is cool & tested it again when it is hot.

I have seen cars pass a pressure test cool but some time when the car gets hot they leak.

 

You'll quickly destroy the engine, if you haven't already, by letting it severely overheat like you do.

 

Double check that fan to make sure it's coming on. My car was doing that a while back, the fan just died on it.

 

Who did the p&p?? IF they hogged out your ports too big they made the cooling jackets too thin, causing the heat issue. Go ahead and ask how I know. It IS WARPED from overheating multiple times now. Service limit on the head is only .002 (cliffs: two thousandths of an inch)How do you think they get warped in the first place? How do you "bore out" a 2.0 to a 1.9 LOL. The only way to downsize displacement without re-sleeving is to de-stroke it with a 1.8 crank...EDIT- your motor is already toast, it'll grenade soon. Epic fail...

 

Most likely.

The public message here is that the temp gauge in the cluster is not just a dash decoration. Monitor the temp gauge regularly and never let the needle rise past the halfway mark before you pull over, turn the engine off, and let it cool.

 

LOL head is NOT warped. So to the 2 people agreeing it is now warped, i just had it torn off and sent back to machine shop. It is FINE. Jackets aren't too thin, fan IS COMING ON, if you read above i mentioned the fan was working. And to S2BumpsticksGSR, you think it's toast? Just got back from drag strip, did 7 pulls on the 1/4 mile and it was fine. Even with a 150 shot....

Compression is good, so not internal issue. And it is sleeved and stuff, titanium rods, ARP rod bolts, ARP studs, titanium valve springs, titanium retainers, cartel cams stage 2 cams, port n polished, larger valves, refinished crank, new oil pump, all new everything.. so if you'd like to continue calling me an "epic fail" enjoy yourself. Meanwhile, i will be on the laguna seca as usual!

went ahead and got a new pressure cap yesterday, it isn't overheating like it was before, but in stop and go traffic it still likes to get a little warm. Please, if you're just gonna say im an idiot or something don't bother. ASE certified in 5 categories, graduated from Automotive School and have a degree in automotive technology. I know how to build motors, just not familiar with Honda.. i'm actually a ford kinda guy, got my 625hp 1988 mustang that's my baby. This is just an auto cross car to race with my buddy.

 

I'm starting to think it's an issue of not having enough fluids. I have a half sized radiator and i daily drive this car so it revs really high. I think i'm going to purchase a full size aluminum racing radiator tonight. This is the same radiator, fan, etc i ran with my last motor and it was fine, and i know my water pump and t-stat is good, so im pondering the idea of lack of fluids. sounds stupid.. but who knows!?

 

Given your expertise, you've got to admit that allowing the temp gauge to reach the HOT red zone is extremely unwise and risky for these Honda engines. But glad to hear your engine did not sustain damage.

 

I understand that letting any engine overheat that isn't an old muscle car is terrible and risky (ive seen some cars have the heads turn red from heat and then cool off and run fine) ... but my gauge is hitting the H, then i put it in 5th and within 20 seconds it's back to normal. I will admit i don't know sh*t about Honda's like I do a ford small block, but im learning as I go. Never believed a 4 banger was fun or fast because everyone out here is a 15 year old kid with a rice burner...but my buddy has a gsr swapped hatch with a jackson blower running 10 psi and it blew my mind away.. so i bought one with him! i'm learning, but thank you all for your input, ordered radiator, should be in tomorrow, will let you all know. Then.. time to save up for injectors, fuel pump, and jackson racing supercharger! Goal is show car, 1/4 mile in the 10's / 11's i'm at sea level), mainly autocross, but still daily drive her. We'll see how it goes, lol. I normally focus on 1320, but my 16 point cage is already inspected and stamped by NHRA and SCCA.. so why not have a muscle car for drag and 4 banger for auto-x? Also, on an unrelated note, does anyone know what distributor i should run? Finding lots of mixed reviews.

 

Could have a faulty thermostat. Just cause its not bad dont mean its not opening at the wrong temp. Try a new one or try running without one an see how it runs. I had the same problem with my car awhile back.. Would only overheat at idle or in stand still traffic. Went through everything an after 2 or 3 different brands of thermostat it stopped. Could be the simple things that make bigger problems. Lmk how it goes..

 

Have you perused the FAQs sticky at the top of this forum, as well as Hybrid forum and the Forced Induction forum? Lots of good stuff there for a guy with your interests, expertise, and enthusiasm.

 

Still cofused how you bore out a 2.0 to a 1.9- expertise my ***. That doesn't work in any engine format. Just because you have expensive parts and deep pockets doesn't even come close to expertise. I'm not claiming to be an expert, but that engines bearings are screwed from being cooked. It won't last long after repeated climbs to the H on the temp gauge. I might not have as much $, but at least I have sense not to jeopardize my engine. EDIT; I'd venture to say you probably have titanium retainers, not springs

 

As i mentioned, im new to the tuner world. Sorry i confused my previous B18b1 and said 1.9. Get off your high horse. I don't have deep pockets, i just drop all my cash into my cars because that is what i live for. I'm not here to start ****, i really enjoy this forum because i've read some amazing builds and founds lots of answers. My engine is jeopardized, like i said, went to track today nd had multiple runs, it handled fine at 9200 rpm's with nitrous. If my bearings didn't go out then, i'm sure i'll be fine! No grinding, no knocking, and it runs great... thanks for your worries though.

 

Please, let's keep this discussion entirely focused on tech rather than making personal remarks.