As usual, I'm running way late. First some pics, then the story.
Here's where we are, since August
We started out at one RV Park, and then switched to here, Lincoln Park Manor RV Park, Site 40.
And a ground level view:
We chose the last of the new sites, so we have pretty much of a “yard”.
We headed out the first of August, breaking up the trip into three legs. First stop was North Toledo Bend La. State Park for a couple days of relaxation, then on to Tyler Tx. State Park. We couldn’t find the durn place! The old entrance was closed and we went around in circles on back roads.
Valkyrie always did like to run on the hot side, 210 to 220 degrees. This is apparently not unusual for the Chevy 454. But, with the 112 degree heat outside and moving slow it climbed to the red line! Pulled off the road onto somebody’s front lawn. We went to the house and told the folks what was going on and that we wanted to let the engine cool down. It was an older couple, who invited us in out of the hot. We had a very enjoyable visit. They explained to us how to get to the new park entrance. Seems we had passed it long before. They have a sign on the highway, pointing straight ahead, then nothing. Coming from the other way, we saw another sign pointing straight ahead, about 800 ft from the first sign. The entrance is in the middle with no sign at all. Go figure!
Well, that was our first and last visit there. We had reserved a pull-thru so we could leave the van attached for our overnight stay. On their web page map, it looked great. Well, it wasn’t. Very short, with a bit of blacktop about half our width and sand on the other half. Not level at all. Had to pile up wood under the jacks. The right front tire was off the ground!
Next day we headed for the RV Park, which shall remain unnamed, where we had a long term reservation. We were heading for Savannah, TX so Grandma Cathy could help out Myrtle with the twins to be.
Well, as the outside temperature climbed past 100, Valkyrie started running hotter. Not too far from our destination, in a little 35 MPH speed limit town, the gauge climbed a hair from the red line. No place to pull off. Then something I should have thought of long before hit me. I slid the heater temperature control all the way to hot. The temperature almost instantly dropped from about 250 to 220 and pretty much stayed there. YEA!
Made it to the RV Park with no more problems, vowing to find the problem and fix it. When we went to check in, the guy told us the monthly rate, including electricity, had gone up by $100!! In a week! He said with all the heat some of the RV’s were using as much as $300 a month. No way, I told him. We had reservations, etc. He told us he’d go with the original $475, but if we used more than $155 electricity we’d have to pay the difference. I asked him if we used less, was he going to reimburse us the difference? He got real quiet. The figure he gave says he upped the water charge as well. We never heard of a park charging for water, but he does. 4-cents a gallon or $15 a month. Doing the math says he went up to $25 on that. Also noticed a sign saying Wi-Fi was $50 a month. The rate page said $25, which he had also told us when we made the reservation. We didn’t get it since we have a cell card for the computer.
We did some looking at other parks, but stumbled upon this place, Lincoln Park Manor. It’s huge, but mostly mobile homes and 40 RV sites. A very nice place, well kept up and even a pool. All the mobile homes have skirting and the general feel is like a small town. There’s even a pool that we almost lived in until it got too cool. The price, including everything is $435 a month. That’s pretty good for this area, but a bit on the high side compared to most. Usually it’s about $350 a month with everything and $200 to $230 with separate electricity. The people in the office are super nice.
After we got all settled, I decided to tackle the big job of finding the overheating problem. I had done a lot of research on the ‘net. There are a lot of things about that problem on the 454. About three quarter said that’s just how they are and can run at up to 260 degrees with no problem, and a quarter said it should run at 195. The standard thermostat is 195. The reason is Chevy wanted it to run on the hot side to get better gas mileage. Well, maybe that should be less worse gas mileage. The confusing thing is that it quickly goes up to 210 and mostly stays there unless it’s above 90 degrees or so outside.
One of the things mentioned a lot is that the motorhome water pump has an opposite rotation. To explain, the vehicle can have V-belts or a serpentine belt. With V, rotation is the same as the engine and with serpentine it’s opposite because the belt wraps around and drives from the backside of the belt. Valkyrie has a serpentine, but it doesn’t wrap so is the same as engine rotation. If the wrong pump, it still pumps in the proper direction, but flow is greatly reduced.
First thing I did was run some radiator flush through the system and put in fresh coolant, with some wetting agent that’s supposed to make it run as much as 30 degrees cooler. No difference. Oddly, the radiator, using my infrared thermometer, was hotter at the bottom than at the top, and hotter on the side that goes to the water pump. This is backwards! And it wasn’t very hot at all anywhere.
Okay, time to pull the water pump. I was hoping I could do it from inside, through the floor opening. Long story, and it was a long one, I was able to do it, but realized I couldn’t put in the new one that way. That was okay because it looked like the radiator might be the problem. The old water pump was in fact the correct rotation and really looked pretty new. There seemed to be some pitting on the cast part around the impeller, but the impeller looked like water had never touched it. Got a new, heavy duty motorhome one anyway.
It wasn’t as involved as I had thought to remove the extra transmission cooler, combination A/C condenser and oil cooler, and radiator. Well, the radiator was kind of tough. It’s held in an iron “cage”. Now there are bolts on the sides, with the idea being to remove the bolts, take the top half off and pull the radiator. The only problem is the driver’s side bolts are a frog’s hair from touching a plate and there’s absolutely no way to reach in there and take them off. So had to work the unit just so to lever up and work out. I hoped I could get it back in!
The radiator didn’t look all that bad, but we brought it to a radiator shop. The owner and only worker (it was one of those old-guy-been-at-it-for-years shops) said I really needed to get a 5-core one. Mine was a 4-core. With the price of copper, it would have been almost $800! I asked him to do his magic on mine. He said it had some normal “white stuff”, but didn’t look bad. He ran some water through it and said it flowed fine. I told him no matter, do a regular clean out, rebuild, whatever it was called.
A few days later he called that it was ready, at a lower price than he had quoted. When I picked it up I asked him if he found anything. He said, with a smile, “You won’t have any more trouble.” I tried to get an explanation, but he just kept grinning and repeating that. Seemed odd, but I’ve seen that behavior from “ol’ guys” before.
Got everything in and back together in about half a day. I left the A/C compressor off and got the correct belt for the power steering with no A/C. It didn’t work anyway, and now I could reach the power steering pump to adjust belt tension without tearing out the radiator again.
Cranked up and the temp gauge
soon went up to 210 as usual. But it was much better. Didn't climb much more
and the radiator temps seemed more as they should be, but pretty low. Like 100
to 120. Added coolant until it stayed full, and then put the cap on.
Shut down and cussed and fussed and so forth. Figured maybe had an air bubble.
Let it all cool down and started up. When the temp gauge approached its 210 thing, I started checking with the infrared.
210 at the gauge and the opposite side, 170 at the thermostat. Thermostat temp very slowly climbed up to about 190. Remember the stock thermostat is 195. Did some stuff to get the gauge to climb to 215 or 220 and thermostat temp comes up to 198. Gauge drops down steadily to 210, thermostat temp to 190 and no flow.
Okay. Now, the thermostat is maybe 3/4 inch from the water pump bypass hose. With the hose off you can see the spring right there. The temp gauge is maybe 2-inches off to the side. With the thermostat out you can reach a finger in and touch the sensor. There's nothing between it or on the opposite side. How in the heck is it 20 deg hotter a couple inches away on each side? Obviously the bypass is sucking water along the thermostat spring from someplace, but it is "stagnant" a couple inches on each side.
The heater hose comes from the rear of the manifold. Even with the heater valve closed, there is a bypass to allow water flow back into the radiator. It's an "H" of copper tube. So apparently water from the rear does flow into the radiator and that water is replaced by the regular route of radiator bottom hose to water pump to block. Temps back there are 180 to 190.
So, run down to Autozone and get a 180 thermostat. The heck with the Chevy way of thinking to run it hot. Put it in and cranked up.
As the gauge temp climbs, thermostat temp is down in the 120's to 130's. The gauge slowly climbs to a bit over 190 and thermostat temp hits a bit over 180. Water flow! Gauge 190 to 195, thermostat 180 to 185. It's a 95 deg day. With the electric fan off, the gauge slowly climbs to a little over 195 and something that almost never happened before. The engine fan clutch kicks in, sounding like a jet engine even at slow idle. Gauge drops down to about 190 and fan clutch disengages. This says something is right. The fan clutch senses the air temp coming though the radiator. With the stock 195 thermostat, the radiator apparently never got enough "hot" water in it. The only time I remember hearing the fan before was when the gauge showed over 240!
The gauge mostly shows 5 to 10 deg higher than the thermostat, but occasionally closely matches. Note that actual gauge temp was checked with the infrared, and showed basically the same as the gauge.
Radiator temps came up, with it higher on the driver's side as it should be (cross flow radiator). Heater hose output 180 to 185 most of the time. All in all, temps seemed more "even" on the engine and more in line with what one would expect. Revving up for a bit drops the temps as expected and more evens them out.
That explains why it cooled
down and stayed when I turned the heater temperature up - Flow though the
heater core. That also explains why the radiator was hotter in the bottom half –
the heater return goes into the radiator about halfway up on the passenger
side, the same side as the water pump inlet. Apparently the thermostat almost
never reached opening temperature and any cooling was coming from the heater
core, a small “radiator” with the heater temperature up, and some cooling from
the heater hose loop to the radiator with the heater temperature off.
Next up, the twins’ early arrival.