- This topic has 6 replies, 3 voices, and was last updated 10 years, 2 months ago by
.
- Topic
[b][color=#0000ff]
The Background[/color][/b]I have a 1989 Honda Accord LXi, 2.0L L4 SOHC 16V, 5-speed Manual Trans, 4-dr Sedan, Non-CARB (49 state), Fuel Injection, 249K mi., A20A3 Engine.
Have been working toward the radiator replacement discussed in a prior post. A BIG thank you to those that offered opinions and advice on that job. It has been tremendously helpful! Spent a considerable amount of time buying parts on the net: this piece here, that piece there and those other things way out yonder. Then the inevitable wait for everything to get shipped and arrive.
Also, have been trying to anticipate problems and get an education. Watched several ETCG videos on:
• Radiator replacement (2),
• Bleeding a cooling system
• Understanding & Testing Thermostats
• Extracting broken Bolts
• Removing broken fasteners.
• OEM vs. discount parts
And probably several others that I have forgotten about! But have to say this is an incredible resource! Great! Super! THANK YOU ERIC!So as part of all of this I bought a set of left-handed drill bits with easy outs and bought a set of stripped head extractors. Also splurged on an electric impact wrench – an inexpensive one from HF – more anticipating its use on an exhaust pipe repair.
Decided on doing a more complete job with the radiator since I had already replaced the water pump a few months ago. So unlike the videos, hoses clamps and a thermostat were on the menu. That video on testing the thermostat really caught my eye as I had spent $16 on a thermostat at a big box store – one that looked like the cheapo in the vid – even though this was a “premium” level item [cheapos were going for ~$7!!!]. Since the Honda thermostat was only $4 more, returned the “premium” off brand and ordered the Honda OEM part. More time delays.
What Happened
OK, so thought I’d get a head start on the radiator replacement by doing the Thermostat – a quick job, with some other minor repairs, to get the repair juices flowing.First order of business was getting access to the thermostat and housing. Moved the clutch cable by unclipping it and bungee the cording forward. Removed several sections of the air intake tubing and removed the coil wire from the distributor. Later removed the support bolts and moved (slightly) the fuse box. Sure wish I knew how to pull this and get it the heck out of the way!
OK so some stuff out of the way. Oh wait, while I was doing this I had a clean pan under the radiator drain cock, opened it and removed the radiator cap. In retrospect sure wish I had opened the air bleeder valve too.
Next step was pulling the clamp back and pulling the hose off the thermostat housing. Green residue around the end of the hose suggests that there was a slow leak here for some time.
The spring clamp was well embedded in the hose and reluctant to slide back, so with two pliers (hose & channel locks) I was able to squeeze the clamp and twist & remove the hose. Now the fun starts! Inside the end of this hose was a bunch of caked deposits – clear “hardening of the arteries” apparently from improper maintenance! My Bad!
So on to removing the cover to the thermostat. Loosened both bolts a few turns with the socket wrench and when I hit resistance on the upper bolt, removed the lower bolt. [6mm x 1.0 pitch with 10MM heads] so back to the top bolt and some cranking and all of a sudden here’s the bolt- a shorty! On further inspection, it was an “Oh Sh*T!” the bolt snapped off!
Well not exactly a panic since I had already watched Eric’s videos on this, so I knew what to do and had the tools to do it! Kinda fun that I had a chance to so do something new and use new knowledge.
Then pulling the thermostat out and WHOA! What a nightmare! All kinds of black crud all over this thing and the build up of junk behind it was phenomenal! No gasket was apparent at all and I figured out that the black crud was probably PermaTex Form-A-Gasket or something like it. I also noted a couple of other things: 1)the thermostat looked like the cheapo (“premium” grade) that I had returned, and 2) the marked set point was 195 degrees, where as the service manual [and the OEM parts list] calls for a set point of 180 degrees.So now my “easy” and quick project has expanded. Spent some time scraping and chipping out the calcified deposits from the thermo housing where the gasket seats and from the thermo cover. I noted considerable pitting of the metal (Aluminum) on the inside and particularly the exterior surface where the upper Radiator hose connects. Next, used the brass wire brush to finish up the calcium removal and finally some metal polish to clean up the cover and all of the mating surfaces.
Then on to bolt extraction process. Goodness, while this looks easy enough in the video this was easily the hardest and most time consuming part! Excitedly got my left-handed bits out and loaded the drill. Grrr, the whole thing is just a half-inch too long to get lined up. So stop and move the fuse box and another section of air intake tubing. Then drilling this was a nightmare. Made zero progress with the small bit and only made an indentation with a larger bit. So after a half-hour went searching for new, better quality, left-handed bits. [One sounds like a prankster calling on the phone asking for left-handed bits as apparently they haven’t permeated the local hardware scene?]
Anyway the hardwareman sold me some new titanium regular bits with the admonishment to run them at a VERY slow speed. I already knew the ‘use lots of lube’ from Eric’s video. Now the drilling started to make some progress, but still it probably took me an hour total to do all of the drilling. Argh! “case hardened steel” the hardwareman called it. Probably grade 8 or 10 material? So I suspect I burned up the left-handed bits by running them at a high speed!
So I get through the bolt all the way and excitedly get the screw extractor (easy out?) into the drill. Oh boy this is gunna be cool! Well unfortunately, the screw didn’t move and I didn’t want to push/jam that bit into the hole and squeeze hard on the variable speed drill. No, went easy and I could see that bit (extractor) started to flex. So on to drilling with the next size bit. Then the second extractor did nothing, so I was stuck.
Here’s where I demonstrated my lack of mechanical knowledge and abilities. I have no set of metric taps. So I decided that “there’s more than one way to skin a cat” and decided to over drill the hole and put a bolt and nut on to hold the cover in place. OK, so hole drilled, but no metric stuff in the parts bin so back to the hardware store for a bolt and nut. Added a washer and lock nut for good measure.
So now the easy part, reassemble everything. Lined up the rubber gasket on the thermostat housing and then the thermostat – made sure the air valve on the thermostat was in the up position. Put the cover on and tightened it down with the factory bolt and my “work around”. You better believe I used plenty of “anti-seize” compound on those bolts!Scraped some more crud out of the end of the upper hose and wiped it out with a cloth. Put it back on the thermo housing and installed a new band clamp. Instead of placing the clamp over the inset area, I placed it over the outer ridge area. I figure this is where the sealing action occurs anyway so why not clamp it there rather than on the pitted metal?
Refilled the radiator with the air bleeder valve open and followed Erics procedures for refilling and bleeding the system. Took about 20 minutes to get the radiator fan to start up on this 40 degree day. Let it cycle a couple of times before topping off and putting the cap back on. No leaks around the thermostat housing in spite of NOT using PermaTex and relying on the metal to metal mating on the outer surface. Whole nightmare took me over 4-hours!
[b][color=#0000ff]
The Questions[/color][/b]- Have not yet replaced the radiator, but seeing all of the crud, build-up and “hardening of the arteries” on this car I am wondering if it wouldn’t be important to “fix” that BEFORE installing the new radiator? Why add new veins that will only get clogged up by the junk in the system?
- On the other hand, with this severe level of build up, perhaps leaving well enough alone is the way to go? Maybe that is why the radiator all of a sudden began to leak after I replaced the water pump? [I did a chemical flush before refilling the coolant.] So if I get aggressive while removing the deposits is it likely I’m going to remove a deposit that is covering a corroded section and that would result in more leaks?
- If I do put something to flush the system – What to use? I used a 10-Minute Flush made by Bars Leak last time. Use that again and run it for a few days? Use a double dose of the stuff? Advice?
- Why the heck did the technician goop up the thermostat with so much permatex? When I replace the water pump, I asked the parts guy and he said that with new “rubber” gaskets one doesn’t need permatex. Is this correct?
- Any problem using grade 8 bolts in this repair? Hardwareman says the Grade 8 metric one he sold me are equivalent to English Grade 5. Have noticed that most of the bolts coming off the Honda are grade 10 or better. These bolts have what looks like the Greek letter Theata on it.
- Replies
The rest of the pictures….
Inside of thermostat housing
Cleaned up housing and seat for gasket
Drilling out the broken bolt
Severe pitting on the thermostat cover
Finished repair – no leaks!
Comments? Suggestions? Lashes with a wet noodle?
I think those were studs, not bolts. But maybe I’m wrong.
Does not actually look that bad for the age and mileage.
Black crud is likely cheap rubber seal deteriorated. Especially if you had not quite oil resistant seal.
If I were you, I’d have had ALL hoses to rad replaced. They have plenty of crud inside and are ballooning from age and temperature. They WILL leak.
Same time, replace all those fancy clamps with hose warn gear clamps. 2 per each connection, for wide tight seal. Be careful tightening them. I did crack aluminum neck once simply doing that. Hose clamps are inexpensive and plentiful anywhere.
Won’t hurt to flush it all with water and some calcium deposit solvent. I think they are all about same and automotive simply cost more. Read what it says under active ingredient, then compare prices.The buildup on the neck of the thermostat housing is just due to the hose connection there leaking for a long time. The housing doesn’t look so good but since you got it to seal, good enough. All the thermostat needs is the rubber gasket to seal.
[quote=”ukrkoz” post=122645]
Black crud is likely cheap rubber seal deteriorated. Especially if you had not quite oil resistant seal.[/quote]
Wonder who put a second seal on the downstream side of the thermostat? Is this standard practice for techs?
[quote=”ukrkoz” post=122645]
If I were you, I’d have had ALL hoses to rad replaced. They have plenty of crud inside and are ballooning from age and temperature. They WILL leak.
Same time, replace all those fancy clamps with hose warn gear clamps. 2 per each connection, for wide tight seal. Be careful tightening them. I did crack aluminum neck once simply doing that. Hose clamps are inexpensive and plentiful anywhere. [/quote]Thanks good advice. I plan on doing that when I replace the radiator. But that will take care of some of the crud. Can only imagine how much crud is in the rest of the engine, heater, etc.
[quote=”ukrkoz” post=122645]Won’t hurt to flush it all with water and some calcium deposit solvent. I think they are all about same and automotive simply cost more. Read what it says under active ingredient, then compare prices.[/quote]
Are you saying i could use something like CLR in there?
[quote=”barneyb” post=122654]The buildup on the neck of the thermostat housing is just due to the hose connection there leaking for a long time. The housing doesn’t look so good but since you got it to seal, good enough. [/quote]
I wonder if the interaction with oxygen on the outside is the reason for the severe corrosion on the outside surfaces of the thermostat cover? Seems to me like the erosion was deeper on the outside than the inside surfaces. Might be another reason to fix leaks? (avoid corrosion)
Funny thing is that I had a shop pressure test the cooling system after doing the water pump. They mentioned a radiator leak and said nothing about leaks at the thermostat. Sigh.
[quote=”barneyb” post=122654]All the thermostat needs is the rubber gasket to seal.[/quote]
Again, wondering why there is a gasket or permatex on the downstream side?
Engines these days either have lots of aluminum parts or are all aluminum. So, the antifreeze, which has anti corrosion additives, needs to be kept fresh. The increased corrosion on the outer surfaces I attribute to staying wet but without the flow of antifreeze.
The goop on the thermostat looks like a messy amateur repair.
- You must be logged in to reply to this topic.