Engine Heat and Splash Pans..... Good or Bad?

[Lawrence Helfand]

My 41 Century has its original engine splash pans which are well scribe'd to the motor and keep any air movement or convection from occurring after its parked. Although it has working hood vents cool air from the ground level cannot circulate and engine bay temperature soars encouraging vapor lock. I will usually  pop the hood after running to help some. I am thinking removing the splash pans will help a lot with post run temperature soar. It always stays at 180 unless sitting in traffic where it will rise some and again with the 4 blade fan at a pretty slow idle it does not seem like much air can circulate. I have a Summit fan not yet installed as overheating has not been an issue with modern re coring of radiator two years ago. It does seem most 41's I see are missing the splash pans so I wonder if this was a dealer suggestion or lazy mechanics? I have never had a car get so hot under the hood after a drive and the only one with splash pans. Anyone with practical experience with splash pan removal and results? 

[Mark Shaw]

Air moves more freely through the radiator without them, & even when parked the radiator will allow cooler air from under the car to flow out of the engine compartment.

[RiKi5156B]

Lazy mechanics I would say. That’s why so many car are also missing spark plug covers.

[kgreen]

Given the road conditions at the time these cars were produced, I see a couple designs more appropriate for gravel/dirt road travel that may find no or little use these days.  Splash pans under the engine for those water filled pot holes on roads, coil-wound rear brake lines to keep rocks from puncturing the brake line, a gravel shield between the bumper and tail pan and possibly the stone guard on thr front portion of rear fenders.  As for the retained heat around an engine with the splash shields, the first owners of these cars didn't have to deal with alcohol contaminated fuel either.

 

[Spinneyhill]

Are they really splash pans? When running, they direct air to the rear of the engine, aiding cooling there. If they are removed, does the rear of the engine run a little hotter?

[Lawrence Helfand]

2 hours ago, Spinneyhill said:

Are they really splash pans? When running, they direct air to the rear of the engine, aiding cooling there. If they are removed, does the rear of the engine run a little hotter?

If it was an air cooled engine maybe but whats important is air flow through the radiator which might be better with easier exit from the engine compartment. I do think the pans were to keep engine clean and dry which they do well. I have had cars with air shrouds and radiator cowls to increase airflow velocity through the radiator but not really to air cool the motor. 

[Dave39MD]

I read a thread on another forum that was discussing this same topic. The experts there felt the removal of the pans adversely effected engine cooling because it disrupted air flow as Spinneyhill mentions above.  It may have something to do with the fact that many cars with pans do not have fan shrouds?

 

Dave

[Matt Harwood]

No splash pans on my '41 Limited and it runs ice cold (160-ish under all circumstances). I don't know if they were there for air management but I suspect that keeping the engine compartment dry was their primary function. I can't see how airflow would be adversely affected by their removal but I also don't know how removing them would improve heat soak when you park--I don't think there's much convection going on that would cool the engine when parked, shields or no shields. Try removing them and see what happens. If it gets hotter when you drive, then you know you need them. If not, don't worry. 

 

I agree, the missing pans are entirely due to lazy mechanics. My Audi had a belly pan that you had to remove to change the oil and it was a real pain. The first time I took it somewhere other than my driveway to have the oil changed, the belly pan disappeared. Had to buy a new one on eBay--what a treat that was to ship! It's totally laziness that causes missing pieces.

[Terry Wiegand]

Matt, my 1916, 1920, and 1922 (all 6-Cylinder) left Flint with belly pans on them.  I have had several old time Buick mechanics and folks very knowledgeable about the early models operation tell me that the first thing that was taken off the car and discarded was the belly pan.  Air flow through the radiator was restricted and caused the engine to run hot to hotter.  This makes good sense to me and especially good sense on the 1916.  The radiator was short and lacking in total cooling surface area.  I have a belly pan for the car but it will hang on my shop wall for that very reason.

 

Terry Wiegand

South Hutchinson, Kansas 

[Grimy]

I agree with Matt to try with and without to see if problems are reduced or aggravated--this may vary by make and model.  Belly pans (as on my 1918 Pierce) are indeed a huge PIA today (must be removed to change the lower radiator hose, for example) but were necessary for the road conditions of the time, and especially to protect the Pierce's external, exposed oil pump and lines.  What we are calling splash pans were called "DUST pans" by much of the repair literature of the 1920s-1930s, again reflecting the road conditions of the day.  If you have at the base of your steering column a headlight switch and spark and throttle control linkage, splash/dust pans are helpful today.  Pragmatically, assuming show points are not a consideration, is there a benefit in retaining them for YOUR driving?  Your call. 

[Guest]

GM could never make up their mind, even in one division they call the same thing by two different names in two different books. Using Pontiac (sorry but she is Buick's little sister or maybe niece) which are the books I have on hand.

 My "Pontiac Repair Parts List" calls them 527656 ENGINE SIDE APRON ASSSEMBLY, R.H.

Looking this up in the 1925-1934 Parts Book shows nothing. 

HOWEVER

 In group 8.112  527656 PAN, Engine side, R.H.

[DonMicheletti]

I have had my '38 Roadmaster for over 30 years. I have always run it with the "splash" pans and have never had overheating problems even when in traffic on hot days.

However I was meticulous about cleaning the water passages in the engine when I redid the engine when I got the car.

The back end of the block had lots of scale and crud.

[Guest]

I concur with Don on the natural tendancy for straight eights to collect sediment at the rear of cooling passages. Thats why I was a bit drastic and cleaned mine with muratic acid. It hurts just about everything but cast iron and will etch even that if left too long, but man did it clean that crap out! Opinions are like... oh nevermind! When I ran my 320 after cleaning it could sit and idle in what we in MN call hot summer weather and not budge the needle verified by quick touch on radiator tank. Ive only found the one pan and I got off a 41 Roadmaster, Buick parts book says Cent and Roadmaster pans same 1941, but parts book description was confusing as it mentioned upper, lower, front, rear. A picture of the pans would be great as I would like to find the complete set whatever that is. Thanx!

[rodneybeauchamp]

Would it be practical to put a series of  air vents or louvres in them as the do on the hoods of many hot rods. Still have an apron but ventilated.

just my two bobs worth

[MCHinson]

3 hours ago, rodneybeauchamp said:

Would it be practical to put a series of  air vents or louvres in them as the do on the hoods of many hot rods. Still have an apron but ventilated.

just my two bobs worth

 

They have louvers in them.

 

My 1937 Century has the pans. It also runs cool. I never would think that they need to be removed although they are a bit of a pain to work around when dropping the oil pan. If a car is overheating, clean out the water jacket and make sure the bypass valve is not the problem and you will cure most overheating issues. If not, then look closely at the radiator condition.

[Lawrence Helfand]

1 hour ago, MCHinson said:

 

They have louvers in them.

 

My 1937 Century has the pans. It also runs cool. I never would think that they need to be removed although they are a bit of a pain to work around when dropping the oil pan. If a car is overheating, clean out the water jacket and make sure the bypass valve is not the problem and you will cure most overheating issues. If not, then look closely at the radiator condition.

My 41 pans have no louvers. I guess the 37 has them? and then were eliminated? Interesting

[kgreen]

Here's a set of '36 splash pans:

 

and a set of '40 splash pans:

One cooling problem on '40 models can occur if the part on the bottom of the photo is missing (the one that looks like an inverted mustache).  This part makes sure that all air taken in at the grill is funneled through the radiator.  Without that part you can get bypass that reduces cooling capacity.