2.8l radiator v6 space issues

[SIVAllan]

I've reached the point where my Series 1 radiator can go to the shop to be modified and wanted to summarize space issues that I've encountered and solutions.

First, the single groove 2.8l v6 harmonic balancer/crankshaft pulley is recessed very little in the center.

The center bolt-head accordingly sticks out past the pulley's flat surface by ~3 mm or 1/8 inch.

The Volvo fan blade fabricated by Dennis M. hits the side of the bolt-head approximately in the center, or ~1.5 mm (1/16 inch) out from the pulley.

The bolt uses a ~1 mm thick washer. If thread lock is acceptable, the clearance problem could be reduced from 1.5 mm to .5 mm or 1/32 inch by omitting the washer.

A spacer at the fan belt pulley to move the fan blade away from the engine can solve the problem and Dennis makes one available although it is 5/8 inch thick (Dennis can verify if that thickness is correct.)

The Volvo fan blade with custom fabricated center is really nice and well worth adapting a spacer.

The distance forward to the radiator - into which the fan blade must move - is tight at ~1/4 inch.

This 1/4 inch must accommodate the fan, which must move forward enough to clear the bolt and spin freely without moving into the radiator.

The Series 1 radiator sits on raised feet that can be modified to be flush with the back wall of the radiator (like a late series radiator) and provide more space - up to 1/2 inch.

The next hurdle is the Series 1 crossflow radiator which sits at an angle with the top sloping down across the engine bay.

The driver's side is an inch or so higher than the passenger's side - and is even with the top of the chassis above the radiator opening.

For the high end to be moved forward 1/2 inch would require a slight trim in the chassis wall to allow the radiator to go forward.

This looks doable with a little planning.

I plan to visit a machine shop in the near future to check costs to fabricate a spacer in 3 different thicknesses - 1/4 inch, 1/8 inch and 1/16 inch.

If there is interest I will inquire into a small run of 10 of each size, or whatever number is required to get a discount.

The spacer(s) would fit like a big washer outside the fan pulley with an inch center hole plus the 4 holes for the fan blade bolts. The spacers could be used individually or stacked as needed.

Interestingly, the radiator turned out to be a 3 core radiator. Maybe all the early series radiators are 3 core, or maybe this one was modified by a prior owner.

 

[Paul A]

Allan and others doing or considering the V6 installation

You can save yourself a lot money, time and grief by using electric fan(s).
You avoid all the issues associated with the limited space between the radiator and the water pump pulley.

I have a single 12" pusher fan on Ol' Blue - the Series V I recently drove to the Ohio United event.

I have twin 8" puller fans on my other V6. I have had no overheating issues with either installation. Neither has a shroud. I suspect they might be even more efficient if a shroud were installed. The fans can be installed to run full time or to activate based on engine temp.

Temps this summer in sunny South Dakota were frequently in the middle to high 90's. Also, I have AC on Ol' Blue. Overheating was never an issue.

 

[SIVAllan]

Allan and others doing or considering the V6 installation

You can save yourself a lot money, time and grief by using electric fan(s).
You avoid all the issues associated with the limited space between the radiator and the water pump pulley.

I have a single 12" pusher fan on Ol' Blue - the Series V I recently drove to the Ohio United event.

I have twin 8" puller fans on my other V6. I have had no overheating issues with either installation. Neither has a shroud. I suspect they might be even more efficient if a shroud were installed. The fans can be installed to run full time or to activate based on engine temp.

Temps this summer in sunny South Dakota were frequently in the middle to high 90's. Also, I have AC on Ol' Blue. Overheating was never an issue.

Didn't take long to hijack the thread

 

[V6 JOSE]

Hi Allen,

You´ll need to trim the fan blades so that they will clear the crank bolt and anything else it might come close to. Since the fan blades areplastic, they are easy to trim.

Jose

Didn't take long to hijack the thread

 

[Paul A]

Didn't take long to hijack the thread

????????????

 

[SIVAllan]

Hi Jose,

It can be done although that's a fair amount of trimming.

The area to be trimmed would remove perhaps 1/4 inch along the inside of each fan blade on the engine side.

I don't know that the plastic blades flex so, if not, the area to be removed could be kept to a minimum.

Trimming the blade presents the great advantages of conserving space as well as money.

Presumably trimmed blades would still move enough air, and there are no issues of balance at higher RPMs?

But either way - trimming or spacers, the fan needs to be re-positioned a little further from the engine.

A third option for positioning the fan would include the use of longer bolts that hold the fabricated center piece to the fan plus a thick spacer on each bolt.

This would shift the fan outward. This seems potentially unwieldy but torque-able bolts should enable consistency and strength.

 

[V6 JOSE]

Hi Allan,

You might want to talk to Dwain Cooke, since he has done this on his fan. His fan will still push a ton of air. He might have some pictures he can show you so you can get the idea. The fan blades will not flex under high rpms.

Jose

Hi Jose,

It can be done although that's a fair amount of trimming.

The area to be trimmed would remove perhaps 1/4 inch along the inside of each fan blade on the engine side.

I don't know that the plastic blades flex so, if not, the area to be removed could be kept to a minimum.

Trimming the blade presents the great advantages of conserving space as well as money.

Presumably trimmed blades would still move enough air, and there are no issues of balance at higher RPMs?

But either way - trimming or spacers, the fan needs to be re-positioned a little further from the engine.

A third option for positioning the fan would include the use of longer bolts that hold the fabricated center piece to the fan plus a thick spacer on each bolt.

This would shift the fan outward. This seems potentially unwieldy but torque-able bolts should enable consistency and strength.

 

[Imperialist1960]

Volvo fan clearance

I notched each of the fan blades with a bolt-head-shaped vacancy.

To do so, I notched one blade so that it cleared.
I then removed the fan from the car.
I shaped the notch to my aesthetic satisfaction, double checked it by reinstalling.

Last step was to replicate the notch.

To do this, I put a piece of blue masking tape on the trailing edge of the notched blade, trimmed it with a razor blade, peeled it off, and stuck it on another fan blade, repeated, and used the tape as a template on each one so that all of the notches are the same.

I used dykes (cutters) to make the first cut and then bumped the blades against the bench grinder to do the finish work.

All of the notches are so similar that I can't tell the difference - looks like its supposed to be that way and is consistent.

Your mileage may vary.

 

[V6 JOSE]

Hi Kenyon,

Thanks for thr testimony of your own experience. You found a good way to make the notches all identical. An engine driven fan is better than an electrical one, because it will never blow a fuse at a most unopportune time and cause the engine to overheat.

Putting an electric fan in front of the radiator is not recommended even by the fan manufacturers themselves. When I bought back my first V6 Alpine, the guy I bought it from had placed two electric fans behind the radiator, and they were thermostatically controlled (supposedly). What I found out was that they had to have been running all the time. I had a fuse go out on me on a cool day, on the freeway, and the engine overheated. At the speed I was going, even if there was no fan of any kind, it would have run cool, but the still fans blocked the air flow through the radiator, causing the engine to over heat.

The electric fans are easy to install, but they are not ideal for this conversion. I know that some guys are using electric fans on their conversions without any problems, but they are still subject to electrical failures, where the engine driven fan (mechanical) will never quit on you, unless you break a fan belt, and at that time you´d better stop because there will be no water circulation and the engine will over heat..

Jose

I notched each of the fan blades with a bolt-head-shaped vacancy.

To do so, I notched one blade so that it cleared.
I then removed the fan from the car.
I shaped the notch to my aesthetic satisfaction, double checked it by reinstalling.

Last step was to replicate the notch.

To do this, I put a piece of blue masking tape on the trailing edge of the notched blade, trimmed it with a razor blade, peeled it off, and stuck it on another fan blade, repeated, and used the tape as a template on each one so that all of the notches are the same.

I used dykes (cutters) to make the first cut and then bumped the blades against the bench grinder to do the finish work.

All of the notches are so similar that I can't tell the difference - looks like its supposed to be that way and is consistent.

Your mileage may vary.

 

[SIVAllan]

Thanks Jose and Kenyon,

The information on "notching" the end of the fan blade to let it clear the crank bolt is very helpful.

The procedure sounds easy to do with simple tools.

Before I "whittle" on the fan blade however I want to reposition the fan blade outward a little bit by other means and see if I can find a good fit.

If not then I'll modify the fan blade.

I measured the distance from the bolt to the radiator core and am obtaining a spacer to put the fan blade half way.

In my case the spacer is 5/32 inch thick and will fit outside the fan belt pulley.

It will be ready by the end of the week/first of the week and I'll let you'all know how it works out.

 

[pcmenten]

Jose' brought up the subject of engine-driven fans vs. electrical fans. I'm torn between the power advantages of using electrical fans and Jose's experience with blown fuses and overheating. Obviously, using electrical fans adds an electrical load, which militates for the use of higher output alternators. It gets into a vicious cycle of upgrades.

Some engine-driven fans have a viscous clutch that engages when it reaches a particular temperature. The fan free-wheels when cold but engages as the temperatures reaches a certain temperature. I like the concept. Also, I know that some pulleys, such as air conditioning pulleys, are electrically operated and wonder why that has not been used on a fan pulley.

Just thinking out loud.

Paul

 

[V6 JOSE]

Hi Paul,

The viscous drive fans will not fit because they make the engine way too long. They work well, but the Alpine engine compartment is just too short.

Jose

Jose' brought up the subject of engine-driven fans vs. electrical fans. I'm torn between the power advantages of using electrical fans and Jose's experience with blown fuses and overheating. Obviously, using electrical fans adds an electrical load, which militates for the use of higher output alternators. It gets into a vicious cycle of upgrades.

Some engine-driven fans have a viscous clutch that engages when it reaches a particular temperature. The fan free-wheels when cold but engages as the temperatures reaches a certain temperature. I like the concept. Also, I know that some pulleys, such as air conditioning pulleys, are electrically operated and wonder why that has not been used on a fan pulley.

Just thinking out loud.

Paul

 

[Imperialist1960]

Notching vs spacing

I tried to avoid notching.

I've had two of three people who have seen the car on my lift snicker about the notches already, although I thought myself very clever.

When you are doing your figuring, keep in mind that there is a locating pin on the nose of the water pump which ensures concentricity. You must get the fan over that thing to install it, and spacers are problematic unless you get a disc that matches the fan bolt holes and concentricity locating pin, I suppose. If I moved the fan out with one, I would lose concentricity unless said spacer was centered on the fan adapter plate, had a concentric locating hole, and was then welded onto the fan center (?).

The radiator that I have must tilt rearwards to come in/out, so no installing the fan first and dropping radiator in after, either - radiator needs the room provided by fan's absence.

I have about 1cm from front of fan to rear of radiator. I suppose that I could have cleared the bolt with a spacer, but then how in the heck would I get the bolts in and a wrench on them if close enough to radiator to miss crank nut?

Chicken and egg feud here on that. Notching's the way to go I say.

Keep in mind that I don't have a Sunbeam radiator, so my measurement won't mean much in comparison to your rig I suppose...

 

[SIVAllan]

Kenyon,

My spacer was ready early so I tried a quick fitment to see how it works.

It works just fine

(I did make an error of measurement as it is a little bit too thin but that is an easy fix.)

The water pumps on my 1974 engine and spare 1974 core do not have the locating pin that you mention so that's a curious occurrence.

My fan now spins freely without any trimming.

The issue regarding radiator installation caused a problem. Getting the fan on without the radiator in place was easy but that left little room for sliding in the radiator.

In fact, the tall feet on my Series 1 radiator made it impossible. The Series 1 radiator would need to be installed first, then the engine, then the transmission.

The T-5 tranny is very long and further complicates things as the engine must come forward when the T5 is hooked up, then slid backwards into the X frame.

But....a Series V radiator that I have fit into place easily with no problem at all ....

The Series V radiator feet are not raised - they are flat with their side of the radiator.

As I folded flat the raised lip surrounding the radiator opening in the chassis, the Series V radiator slid into place leaving perhaps 1/4 to 1/3 inch between it and the fan - I didn't have time to measure it.

I'll need to shorten the feet on the Series 1 radiator so that it slides in as easily as the Series V radiator and then ... problem solved.

Trimming the fan is certainly a good option, whether a notch is made or whether the notch is extended the length of the blade for aesthetic reasons, but trimming isn't the only option.

 

[Chuck Ingram]

Of course everyone has checked that the fan is balanced when cutting or trimming

 

[Bill Blue]

Of course everyone has checked that the fan is balanced when cutting or trimming

Not at all. The nylon is not all that heavy and if the trim is about the same on each blade, you will not have any problem.

Bill

 

[Imperialist1960]

Of course everyone has checked that the fan is balanced when cutting or trimming

If the fan being modestly out of balance is the biggest failure to manifest itself when I am fettling the car, I will buy a case of beer for everyone within the sound of my keyboard here.

I bought the transmission used off of CL from a bro with a big gold chain around his neck, adapted a complete 4-wheel disc brake system from another car, and built the engine and trans mount myself after buying the car shell as a basket case for $500.

I can therefore afford to live dangerously on the fan trimming issue, but I appreciate your concern - it is valid.