Clio sport 172 ph2 Fr4 736 engine block

[Capochamdz]

Hello RS commumity,

I had a big failure in a f4r 736, a rod bearing get seized and brocked a rod.
Im looking for a replacement engine block but in argentina is almost impossible to get a 736 block.
Everything that i found has the coolant pump timing belt driven.
The diesel 1.9 or the renault 2.0 8v block will mate? What are the options that i have?

Thanks in advance

 

[bloke]

number two, there's a surprise ?

 

[White16valver]

Could you purchase a replacement block from eBay or another seller overseas?

 

[Capochamdz]

Could you purchase a replacement block from eBay or another seller overseas?

Customs dont allow used parts, and if new is a complex and expensive ger the approval

 

[Capochamdz]

Hi guys,
I found that f4r engines has different castings patterns and aparently is written on one side a top right.
F4
f4a
f4k
Anyone knowns if this is correct and all castings with the same designation will mate?

 

[Capochamdz]

Hi guy, finally we get one almost new

Now im in doubt about the crank and main bearing. 172 ph2 crank is only 4 counterwheight and has only one lube oil per main, and main bearing is only half grooved. What happen with rod when the hole is in area when at the main bearing is not grooved?

F4r 740 crankshaft has a through hole so all time there is a hole open to the main bearing groove.

There is a main bearing full grooved? Anyone recomends to fit full grooved?

 

[White16valver]

You are in territory I have not visited! lol

@Coops Mk1 or @STEVE.M or @Wobba might be able to help??

 

[Coops Mk1]

I'm out on f4r I'm afraid, not that up on the newer engines, I'm an f7 boy

 

[Capochamdz]

Here some pics that explain better the situation

172 Crank, has only one hole per main (as it can see, not all mains has a vissible hole)

Crank 182 all mains has trough hole in all mains (pic from F4R 740, that seems to be identical at leat from casting pattern)

Crank Clio III 197, similar to 172 ph2 but with 8 counterweights, seems to have trough hole in all mains

The problem is that with one hole, if main bearing is only half grooved, half of the time there isnt oil supply to rod bearing

ACL and King bearings has a 3/4 groove design as below scheme that bring a better scenario, but still 1/4 of the time without oil supply to rod bearing.

In this topic a guy said that used the grooved half of two sets to have full groove
https://www.cliosport.net/threads/the-life-of-sharkyuks-trophy.461519/page-57


What do you recomend guys?
I see three alternatives
1- Fit full groove bearing with 172 crank
2- Filt 3/4 groove with 172 crank
3- Fit 12 groove with F4R 740 crank

Thanks in advance

Regards

 

[Ol’ Tarby]

@bloke will know

 

[White16valver]

Good research!

Perhaps @SharkyUK might be able confirm his engine builder man's thoughts!

 

[bloke]

there must be literally hundreds of thousands of k4m and f4r engines around, if the lack of grooved bearing was an issue you would know about it, on the whole it's a reliable engine.

i wouldn't bother modifying to run tagged bearings, despite what people say it won't stop a bearing from spinning. oil pump is the issue on them. there are pro's and con's to both drillings on mains and grooved/non grooved shells.

if you want to look into the differences in crank you need to look at how the are cross drilled for the big end as well as there is a difference with them. think i've seen 5 different cranks from phase 1 to 197?

 

[Capochamdz]

there must be literally hundreds of thousands of k4m and f4r engines around, if the lack of grooved bearing was an issue you would know about it, on the whole it's a reliable engine.

You are right, but i think that there isnt a problem when you have a cross drilled main (two holes in main) as most of the ckanks has for that engines.
172 ph2 crank has only one hole in main surfaces.

 

[bloke]

have seen every variation of crank with bearing failure on no2 big end.

 

[SharkyUK]

In this topic a guy said that used the grooved half of two sets to have full groove
https://www.cliosport.net/threads/the-life-of-sharkyuks-trophy.461519/page-57

Good research!

Perhaps @SharkyUK might be able confirm his engine builder man's thoughts!

The F4R is typically very poor (or can be) when it comes to oil pressure, hence I had a restrictor added as insurance to help ensure that an adequate oil pressure is maintained within the engine. In addition, I also had the fully grooved main bearings for a bit of extra insurance - by helping to provide a film of oil around the full circumference of the crank journal.